Renamed: adaptglok -> fire2
3
.github/CONTRIBUTING.md
vendored
@ -68,7 +68,8 @@ How quickly your contribution will be integrated depends largely on how much eff
|
||||
Here is a checklist of steps you need to follow to submit a single file or user package for our consideration. Following these steps will save both you and us time. See existing files in packages in the source directory for examples. If you are uncertain, please ask on the lammps-users mailing list.
|
||||
|
||||
* All source files you provide must compile with the most current version of LAMMPS with multiple configurations. In particular you need to test compiling LAMMPS from scratch with `-DLAMMPS_BIGBIG` set in addition to the default `-DLAMMPS_SMALLBIG` setting. Your code will need to work correctly in serial and in parallel using MPI.
|
||||
* For consistency with the rest of LAMMPS and especially, if you want your contribution(s) to be added to main LAMMPS code or one of its standard packages, it needs to be written in a style compatible with other LAMMPS source files. This means: 2-character indentation per level, no tabs, no lines over 80 characters. I/O is done via the C-style stdio library, style class header files should not import any system headers outside of <cstdio>, STL containers should be avoided in headers, and forward declarations used where possible or needed. All added code should be placed into the LAMMPS_NS namespace or a sub-namespace; global or static variables should be avoided, as they conflict with the modular nature of LAMMPS and the C++ class structure. There MUST NOT be any "using namespace XXX;" statements in headers. In the implementation file (<name>.cpp) system includes should be placed in angular brackets (<>) and for c-library functions the C++ style header files should be included (<cstdio> instead of <stdio.h>, or <cstring> instead of <string.h>). This all is so the developers can more easily understand, integrate, and maintain your contribution and reduce conflicts with other parts of LAMMPS. This basically means that the code accesses data structures, performs its operations, and is formatted similar to other LAMMPS source files, including the use of the error class for error and warning messages.
|
||||
* For consistency with the rest of LAMMPS and especially, if you want your contribution(s) to be added to main LAMMPS code or one of its standard packages, it needs to be written in a style compatible with other LAMMPS source files. This means: 2-character indentation per level, no tabs, no lines over 80 characters. I/O is done via the C-style stdio library, style class header files should not import any system headers, STL containers should be avoided in headers, and forward declarations used where possible or needed. All added code should be placed into the LAMMPS_NS namespace or a sub-namespace; global or static variables should be avoided, as they conflict with the modular nature of LAMMPS and the C++ class structure. There MUST NOT be any "using namespace XXX;" statements in headers. In the implementation file (<name>.cpp) system includes should be placed in angular brackets (<>) and for c-library functions the C++ style header files should be included (<cstdio> instead of <stdio.h>, or <cstring> instead of <string.h>). This all is so the developers can more easily understand, integrate, and maintain your contribution and reduce conflicts with other parts of LAMMPS. This basically means that the code accesses data structures, performs its operations, and is formatted similar to other LAMMPS source files, including the use of the error class for error and warning messages.
|
||||
* Source, style name, and documentation file should follow the following naming convention: style names should be lowercase and words separated by a forward slash; for a new fix style 'foo/bar', the class should be named FixFooBar, the name of the source files should be 'fix_foo_bar.h' and 'fix_foo_bar.cpp' and the corresponding documentation should be in a file 'fix_foo_bar.txt'.
|
||||
* If you want your contribution to be added as a user-contributed feature, and it is a single file (actually a `<name>.cpp` and `<name>.h` file) it can be rapidly added to the USER-MISC directory. Include the one-line entry to add to the USER-MISC/README file in that directory, along with the 2 source files. You can do this multiple times if you wish to contribute several individual features.
|
||||
* If you want your contribution to be added as a user-contribution and it is several related features, it is probably best to make it a user package directory with a name like USER-FOO. In addition to your new files, the directory should contain a README text file. The README should contain your name and contact information and a brief description of what your new package does. If your files depend on other LAMMPS style files also being installed (e.g. because your file is a derived class from the other LAMMPS class), then an Install.sh file is also needed to check for those dependencies. See other README and Install.sh files in other USER directories as examples. Send us a tarball of this USER-FOO directory.
|
||||
* Your new source files need to have the LAMMPS copyright, GPL notice, and your name and email address at the top, like other user-contributed LAMMPS source files. They need to create a class that is inside the LAMMPS namespace. If the file is for one of the USER packages, including USER-MISC, then we are not as picky about the coding style (see above). I.e. the files do not need to be in the same stylistic format and syntax as other LAMMPS files, though that would be nice for developers as well as users who try to read your code.
|
||||
|
||||
@ -52,10 +52,17 @@ check_for_autogen_files(${LAMMPS_SOURCE_DIR})
|
||||
include(CheckCCompilerFlag)
|
||||
include(CheckIncludeFileCXX)
|
||||
|
||||
if (${CMAKE_CXX_COMPILER_ID} STREQUAL "Intel")
|
||||
if(${CMAKE_CXX_COMPILER_ID} STREQUAL "Intel")
|
||||
set (CMAKE_CXX_FLAGS "${CMAKE_CXX_FLAGS} -restrict")
|
||||
endif()
|
||||
|
||||
option(DISABLE_CXX11_REQUIREMENT "Disable check that requires C++11 for compiling LAMMPS" OFF)
|
||||
if(DISABLE_CXX11_REQUIREMENT)
|
||||
add_definitions(-DLAMMPS_CXX98)
|
||||
else()
|
||||
set(CMAKE_CXX_STANDARD 11)
|
||||
endif()
|
||||
|
||||
# GNU compiler features
|
||||
if (${CMAKE_CXX_COMPILER_ID} STREQUAL "GNU")
|
||||
option(ENABLE_COVERAGE "Enable code coverage" OFF)
|
||||
@ -315,13 +322,14 @@ endif()
|
||||
include(Packages/KSPACE)
|
||||
include(Packages/PYTHON)
|
||||
include(Packages/VORONOI)
|
||||
include(Packages/USER-SCAFACOS)
|
||||
include(Packages/USER-PLUMED)
|
||||
include(Packages/USER-COLVARS)
|
||||
include(Packages/USER-MOLFILE)
|
||||
include(Packages/USER-NETCDF)
|
||||
include(Packages/USER-SMD)
|
||||
include(Packages/USER-QUIP)
|
||||
include(Packages/USER-PLUMED)
|
||||
include(Packages/USER-QMMM)
|
||||
include(Packages/USER-QUIP)
|
||||
include(Packages/USER-SCAFACOS)
|
||||
include(Packages/USER-SMD)
|
||||
include(Packages/USER-VTK)
|
||||
include(Packages/KIM)
|
||||
include(Packages/LATTE)
|
||||
@ -411,8 +419,7 @@ endforeach()
|
||||
##############################################
|
||||
# add lib sources of (simple) enabled packages
|
||||
############################################
|
||||
foreach(SIMPLE_LIB POEMS USER-ATC USER-AWPMD USER-COLVARS USER-H5MD
|
||||
USER-QMMM)
|
||||
foreach(SIMPLE_LIB POEMS USER-ATC USER-AWPMD USER-H5MD USER-QMMM)
|
||||
if(PKG_${SIMPLE_LIB})
|
||||
string(REGEX REPLACE "^USER-" "" PKG_LIB "${SIMPLE_LIB}")
|
||||
string(TOLOWER "${PKG_LIB}" PKG_LIB)
|
||||
@ -426,10 +433,6 @@ foreach(SIMPLE_LIB POEMS USER-ATC USER-AWPMD USER-COLVARS USER-H5MD
|
||||
target_include_directories(awpmd PUBLIC ${LAMMPS_LIB_SOURCE_DIR}/awpmd/systems/interact ${LAMMPS_LIB_SOURCE_DIR}/awpmd/ivutils/include)
|
||||
elseif(PKG_LIB STREQUAL h5md)
|
||||
target_include_directories(h5md PUBLIC ${LAMMPS_LIB_SOURCE_DIR}/h5md/include ${HDF5_INCLUDE_DIRS})
|
||||
elseif(PKG_LIB STREQUAL colvars)
|
||||
target_compile_options(colvars PRIVATE -DLEPTON)
|
||||
target_include_directories(colvars PRIVATE ${LAMMPS_LIB_SOURCE_DIR}/colvars/lepton/include)
|
||||
target_include_directories(colvars PUBLIC ${LAMMPS_LIB_SOURCE_DIR}/colvars)
|
||||
else()
|
||||
target_include_directories(${PKG_LIB} PUBLIC ${LAMMPS_LIB_SOURCE_DIR}/${PKG_LIB})
|
||||
endif()
|
||||
|
||||
@ -1,15 +1,24 @@
|
||||
if(PKG_KOKKOS)
|
||||
set(LAMMPS_LIB_KOKKOS_SRC_DIR ${LAMMPS_LIB_SOURCE_DIR}/kokkos)
|
||||
set(LAMMPS_LIB_KOKKOS_BIN_DIR ${LAMMPS_LIB_BINARY_DIR}/kokkos)
|
||||
# TODO: this option needs to be documented when this works with a
|
||||
# regular release version of KOKKOS, and a version compatibility check
|
||||
# of external KOKKOS lib versus what the KOKKOS package needs is required.
|
||||
option(EXTERNAL_KOKKOS "Build against external kokkos library")
|
||||
if(EXTERNAL_KOKKOS)
|
||||
find_package(Kokkos REQUIRED)
|
||||
list(APPEND LAMMPS_LINK_LIBS Kokkos::kokkos)
|
||||
else()
|
||||
set(LAMMPS_LIB_KOKKOS_SRC_DIR ${LAMMPS_LIB_SOURCE_DIR}/kokkos)
|
||||
set(LAMMPS_LIB_KOKKOS_BIN_DIR ${LAMMPS_LIB_BINARY_DIR}/kokkos)
|
||||
add_subdirectory(${LAMMPS_LIB_KOKKOS_SRC_DIR} ${LAMMPS_LIB_KOKKOS_BIN_DIR})
|
||||
|
||||
set(Kokkos_INCLUDE_DIRS ${LAMMPS_LIB_KOKKOS_SRC_DIR}/core/src
|
||||
${LAMMPS_LIB_KOKKOS_SRC_DIR}/containers/src
|
||||
${LAMMPS_LIB_KOKKOS_SRC_DIR}/algorithms/src
|
||||
${LAMMPS_LIB_KOKKOS_BIN_DIR})
|
||||
include_directories(${Kokkos_INCLUDE_DIRS})
|
||||
list(APPEND LAMMPS_LINK_LIBS kokkos)
|
||||
endif()
|
||||
add_definitions(-DLMP_KOKKOS)
|
||||
add_subdirectory(${LAMMPS_LIB_KOKKOS_SRC_DIR} ${LAMMPS_LIB_KOKKOS_BIN_DIR})
|
||||
|
||||
set(Kokkos_INCLUDE_DIRS ${LAMMPS_LIB_KOKKOS_SRC_DIR}/core/src
|
||||
${LAMMPS_LIB_KOKKOS_SRC_DIR}/containers/src
|
||||
${LAMMPS_LIB_KOKKOS_SRC_DIR}/algorithms/src
|
||||
${LAMMPS_LIB_KOKKOS_BIN_DIR})
|
||||
include_directories(${Kokkos_INCLUDE_DIRS})
|
||||
list(APPEND LAMMPS_LINK_LIBS kokkos)
|
||||
|
||||
set(KOKKOS_PKG_SOURCES_DIR ${LAMMPS_SOURCE_DIR}/KOKKOS)
|
||||
set(KOKKOS_PKG_SOURCES ${KOKKOS_PKG_SOURCES_DIR}/kokkos.cpp
|
||||
|
||||
42
cmake/Modules/Packages/USER-COLVARS.cmake
Normal file
@ -0,0 +1,42 @@
|
||||
if(PKG_USER-COLVARS)
|
||||
|
||||
set(COLVARS_SOURCE_DIR ${LAMMPS_LIB_SOURCE_DIR}/colvars)
|
||||
|
||||
file(GLOB COLVARS_SOURCES ${COLVARS_SOURCE_DIR}/[^.]*.cpp)
|
||||
|
||||
# Build Lepton by default
|
||||
set(COLVARS_LEPTON_DEFAULT ON)
|
||||
# but not if C++11 is disabled per user request
|
||||
if(DEFINED DISABLE_CXX11_REQUIREMENT)
|
||||
if(DISABLE_CXX11_REQUIREMENT)
|
||||
set(COLVARS_LEPTON_DEFAULT OFF)
|
||||
endif()
|
||||
endif()
|
||||
|
||||
option(COLVARS_LEPTON "Build and link the Lepton library" ${COLVARS_LEPTON_DEFAULT})
|
||||
|
||||
# Verify that the user's choice is consistent
|
||||
if(DEFINED DISABLE_CXX11_REQUIREMENT)
|
||||
if((DISABLE_CXX11_REQUIREMENT) AND (COLVARS_LEPTON))
|
||||
message(FATAL_ERROR "Building the Lepton library requires C++11 or later.")
|
||||
endif()
|
||||
endif()
|
||||
|
||||
if(COLVARS_LEPTON)
|
||||
set(LEPTON_DIR ${LAMMPS_LIB_SOURCE_DIR}/colvars/lepton)
|
||||
file(GLOB LEPTON_SOURCES ${LEPTON_DIR}/src/[^.]*.cpp)
|
||||
add_library(lepton STATIC ${LEPTON_SOURCES})
|
||||
target_include_directories(lepton PRIVATE ${LEPTON_DIR}/include)
|
||||
endif()
|
||||
|
||||
add_library(colvars STATIC ${COLVARS_SOURCES})
|
||||
target_include_directories(colvars PUBLIC ${LAMMPS_LIB_SOURCE_DIR}/colvars)
|
||||
list(APPEND LAMMPS_LINK_LIBS colvars)
|
||||
|
||||
if(COLVARS_LEPTON)
|
||||
list(APPEND LAMMPS_LINK_LIBS lepton)
|
||||
target_compile_options(colvars PRIVATE -DLEPTON)
|
||||
target_include_directories(colvars PUBLIC ${LEPTON_DIR}/include)
|
||||
endif()
|
||||
|
||||
endif()
|
||||
@ -7,7 +7,7 @@ set(ALL_PACKAGES ASPHERE CLASS2 COLLOID CORESHELL DIPOLE
|
||||
PYTHON QEQ REPLICA RIGID SHOCK SRD VORONOI
|
||||
USER-CGDNA USER-CGSDK USER-COLVARS USER-DIFFRACTION USER-DPD
|
||||
USER-DRUDE USER-FEP USER-MEAMC USER-MESO
|
||||
USER-MISC USER-MOFFF USER-OMP USER-PLUMED USER-PHONON USER-REAXC
|
||||
USER-MISC USER-MOFFF USER-OMP USER-PHONON USER-REAXC
|
||||
USER-SPH USER-SMD USER-UEF USER-YAFF)
|
||||
|
||||
foreach(PKG ${ALL_PACKAGES})
|
||||
|
||||
@ -69,6 +69,7 @@ html: $(OBJECTS) $(ANCHORCHECK)
|
||||
sphinx-build $(SPHINXEXTRA) -b html -c utils/sphinx-config -d $(BUILDDIR)/doctrees $(RSTDIR) html ;\
|
||||
echo "############################################" ;\
|
||||
doc_anchor_check src/*.txt ;\
|
||||
env LC_ALL=C grep -n '[^ -~]' src/*.txt ;\
|
||||
echo "############################################" ;\
|
||||
deactivate ;\
|
||||
)
|
||||
|
||||
@ -1,4 +1,4 @@
|
||||
.TH LAMMPS "7 August 2019" "2019-08-07"
|
||||
.TH LAMMPS "19 September 2019" "2019-09-19"
|
||||
.SH NAME
|
||||
.B LAMMPS
|
||||
\- Molecular Dynamics Simulator.
|
||||
|
||||
@ -50,7 +50,7 @@ Code Coverage and Testing :h4,link(testing)
|
||||
|
||||
We do extensive regression testing of the LAMMPS code base on a continuous
|
||||
basis. Some of the logic to do this has been added to the CMake build so
|
||||
developers can run the tests directly on their workstation.
|
||||
developers can run the tests directly on their workstation.
|
||||
|
||||
NOTE: this is incomplete and only represents a small subset of tests that we run
|
||||
|
||||
|
||||
@ -12,6 +12,7 @@ Optional build settings :h3
|
||||
LAMMPS can be built with several optional settings. Each sub-section
|
||||
explain how to do this for building both with CMake and make.
|
||||
|
||||
"C++11 standard compliance test"_#cxx11 when building all of LAMMPS
|
||||
"FFT library"_#fft for use with the "kspace_style pppm"_kspace_style.html command
|
||||
"Size of LAMMPS data types"_#size
|
||||
"Read or write compressed files"_#gzip
|
||||
@ -23,6 +24,28 @@ explain how to do this for building both with CMake and make.
|
||||
|
||||
:line
|
||||
|
||||
C++11 standard compliance test :h4,link(cxx11)
|
||||
|
||||
The LAMMPS developers plan to transition to make the C++11 standard the
|
||||
minimum requirement for compiling LAMMPS. Currently this only applies to
|
||||
some packages like KOKKOS while the rest aims to be compatible with the C++98
|
||||
standard. Most currently used compilers are compatible with C++11; some need
|
||||
to set extra flags to switch. To determine the impact of requiring C++11,
|
||||
we have added a simple compliance test to the source code, that will cause
|
||||
the compilation to abort, if C++11 compliance is not available or enabled.
|
||||
To bypass this check, you need to change a setting in the makefile or
|
||||
when calling CMake.
|
||||
|
||||
[CMake variable]:
|
||||
|
||||
-D DISABLE_CXX11_REQUIREMENT=yes
|
||||
|
||||
[Makefile.machine setting]:
|
||||
|
||||
LMP_INC = -DLAMMPS_CXX98
|
||||
|
||||
:line
|
||||
|
||||
FFT library :h4,link(fft)
|
||||
|
||||
When the KSPACE package is included in a LAMMPS build, the
|
||||
|
||||
@ -124,6 +124,7 @@ An alphabetic list of all general LAMMPS commands.
|
||||
"thermo"_thermo.html,
|
||||
"thermo_modify"_thermo_modify.html,
|
||||
"thermo_style"_thermo_style.html,
|
||||
"third_order"_third_order.html,
|
||||
"timer"_timer.html,
|
||||
"timestep"_timestep.html,
|
||||
"uncompute"_uncompute.html,
|
||||
|
||||
@ -166,6 +166,7 @@ OPT.
|
||||
"lj/smooth/linear (o)"_pair_lj_smooth_linear.html,
|
||||
"lj/switch3/coulgauss/long"_pair_lj_switch3_coulgauss.html,
|
||||
"lj96/cut (go)"_pair_lj96.html,
|
||||
"local/density"_pair_local_density.html,
|
||||
"lubricate (o)"_pair_lubricate.html,
|
||||
"lubricate/poly (o)"_pair_lubricate.html,
|
||||
"lubricateU"_pair_lubricateU.html,
|
||||
|
||||
BIN
doc/src/Eqs/norm_inf.jpg
Normal file
|
After Width: | Height: | Size: 14 KiB |
15
doc/src/Eqs/norm_inf.tex
Normal file
@ -0,0 +1,15 @@
|
||||
\documentclass[preview]{standalone}
|
||||
\usepackage{varwidth}
|
||||
\usepackage[utf8x]{inputenc}
|
||||
\usepackage{amsmath, amssymb, graphics, setspace}
|
||||
|
||||
\begin{document}
|
||||
\begin{varwidth}{50in}
|
||||
\begin{equation}
|
||||
|| \vec{F} ||_{inf}
|
||||
= {\rm max}\left(|F_1^1|, |F_1^2|, |F_1^3| \cdots,
|
||||
|F_N^1|, |F_N^2|, |F_N^3|\right)
|
||||
\nonumber
|
||||
\end{equation}
|
||||
\end{varwidth}
|
||||
\end{document}
|
||||
BIN
doc/src/Eqs/norm_max.jpg
Normal file
|
After Width: | Height: | Size: 9.2 KiB |
15
doc/src/Eqs/norm_max.tex
Normal file
@ -0,0 +1,15 @@
|
||||
\documentclass[preview]{standalone}
|
||||
\usepackage{varwidth}
|
||||
\usepackage[utf8x]{inputenc}
|
||||
\usepackage{amsmath, amssymb, graphics, setspace}
|
||||
|
||||
\begin{document}
|
||||
\begin{varwidth}{50in}
|
||||
\begin{equation}
|
||||
% \left| \left| \vec{F} \right| \right|_2
|
||||
|| \vec{F} ||_{max}
|
||||
= {\rm max}\left(||\vec{F}_1||, \cdots, ||\vec{F}_N||\right)
|
||||
\nonumber
|
||||
\end{equation}
|
||||
\end{varwidth}
|
||||
\end{document}
|
||||
BIN
doc/src/Eqs/norm_two.jpg
Normal file
|
After Width: | Height: | Size: 5.9 KiB |
15
doc/src/Eqs/norm_two.tex
Normal file
@ -0,0 +1,15 @@
|
||||
\documentclass[preview]{standalone}
|
||||
\usepackage{varwidth}
|
||||
\usepackage[utf8x]{inputenc}
|
||||
\usepackage{amsmath, amssymb, graphics, setspace}
|
||||
|
||||
\begin{document}
|
||||
\begin{varwidth}{50in}
|
||||
\begin{equation}
|
||||
% \left| \left| \vec{F} \right| \right|_2
|
||||
|| \vec{F} ||_{2}
|
||||
= \sqrt{\vec{F}_1+ \cdots + \vec{F}_N}
|
||||
\nonumber
|
||||
\end{equation}
|
||||
\end{varwidth}
|
||||
\end{document}
|
||||
BIN
doc/src/Eqs/pair_local_density_energy.jpg
Normal file
|
After Width: | Height: | Size: 3.0 KiB |
11
doc/src/Eqs/pair_local_density_energy.tex
Normal file
@ -0,0 +1,11 @@
|
||||
\documentclass[12pt]{article}
|
||||
|
||||
\begin{document}
|
||||
|
||||
$$
|
||||
U_{LD} = \sum_i F(\rho_i)
|
||||
$$
|
||||
|
||||
|
||||
\end{document}
|
||||
~
|
||||
BIN
doc/src/Eqs/pair_local_density_energy_implement.jpg
Normal file
|
After Width: | Height: | Size: 7.8 KiB |
9
doc/src/Eqs/pair_local_density_energy_implement.tex
Normal file
@ -0,0 +1,9 @@
|
||||
\documentclass[12pt]{article}
|
||||
|
||||
\begin{document}
|
||||
|
||||
$$
|
||||
U_{LD} = \sum_k U_{LD}^{(k)} = \sum_i \left[ \sum_k a_\alpha^{(k)} F^{(k)} \left(\rho_i^{(k)}\right) \right]
|
||||
$$
|
||||
|
||||
\end{document}
|
||||
BIN
doc/src/Eqs/pair_local_density_energy_multi.jpg
Normal file
|
After Width: | Height: | Size: 3.4 KiB |
9
doc/src/Eqs/pair_local_density_energy_multi.tex
Normal file
@ -0,0 +1,9 @@
|
||||
\documentclass[12pt]{article}
|
||||
|
||||
\begin{document}
|
||||
|
||||
$$
|
||||
U_{LD} = \sum_i a_\alpha F(\rho_i)
|
||||
$$
|
||||
|
||||
\end{document}
|
||||
BIN
doc/src/Eqs/pair_local_density_indicator_func.jpg
Normal file
|
After Width: | Height: | Size: 8.8 KiB |
16
doc/src/Eqs/pair_local_density_indicator_func.tex
Normal file
@ -0,0 +1,16 @@
|
||||
\documentclass[12pt]{article}
|
||||
\usepackage[utf8]{inputenc}
|
||||
\usepackage{amsmath}
|
||||
\usepackage{amsfonts}
|
||||
|
||||
\begin{document}
|
||||
\[
|
||||
\varphi(r) =
|
||||
\begin{cases}
|
||||
1 & r \le R_1 \\
|
||||
c_0 + c_2r^2 + c_4r^4 + c_6r^6 & r \in (R_1, R_2) \\
|
||||
0 & r \ge R_2
|
||||
\end{cases}
|
||||
\]
|
||||
|
||||
\end{document}
|
||||
BIN
doc/src/Eqs/pair_local_density_ld.jpg
Normal file
|
After Width: | Height: | Size: 3.0 KiB |
10
doc/src/Eqs/pair_local_density_ld.tex
Normal file
@ -0,0 +1,10 @@
|
||||
\documentclass[12pt]{article}
|
||||
|
||||
\begin{document}
|
||||
|
||||
|
||||
$$
|
||||
\rho_i = \sum_{j \neq i} \varphi(r_{ij})
|
||||
$$
|
||||
|
||||
\end{document}
|
||||
BIN
doc/src/Eqs/pair_local_density_ld_implement.jpg
Normal file
|
After Width: | Height: | Size: 4.2 KiB |
10
doc/src/Eqs/pair_local_density_ld_implement.tex
Normal file
@ -0,0 +1,10 @@
|
||||
\documentstyle[12pt]{article}
|
||||
|
||||
\begin{document}
|
||||
|
||||
|
||||
$$
|
||||
\rho_i^{(k)} = \sum_j b_\beta^{(k)} \varphi^{(k)} (r_{ij})
|
||||
$$
|
||||
|
||||
\end{document}
|
||||
BIN
doc/src/Eqs/pair_local_density_ld_multi.jpg
Normal file
|
After Width: | Height: | Size: 3.4 KiB |
10
doc/src/Eqs/pair_local_density_ld_multi.tex
Normal file
@ -0,0 +1,10 @@
|
||||
\documentclass[12pt]{article}
|
||||
|
||||
\begin{document}
|
||||
|
||||
|
||||
$$
|
||||
\rho_i = \sum_{j \neq i} b_\beta \varphi(r_{ij})
|
||||
$$
|
||||
|
||||
\end{document}
|
||||
@ -4791,6 +4791,22 @@ Self-explanatory. :dd
|
||||
|
||||
This fix option cannot be used with point particles. :dd
|
||||
|
||||
{Fix langevin gjf and respa are not compatible} :dt
|
||||
|
||||
Self-explanatory. :dd
|
||||
|
||||
{Fix langevin gjf cannot have period equal to dt/2} :dt
|
||||
|
||||
If the period is equal to dt/2 then division by zero will happen. :dd
|
||||
|
||||
{Fix langevin gjf should come before fix nve} :dt
|
||||
|
||||
Self-explanatory. :dd
|
||||
|
||||
{Fix langevin gjf with tbias is not yet implemented with kokkos} :dt
|
||||
|
||||
This option is not yet available. :dd
|
||||
|
||||
{Fix langevin omega is not yet implemented with kokkos} :dt
|
||||
|
||||
This option is not yet available. :dd
|
||||
|
||||
@ -47,6 +47,11 @@ too far away. :dd
|
||||
|
||||
Self-explanatory. :dd
|
||||
|
||||
{Angles are defined but no angle style is set} :dt
|
||||
|
||||
The topology contains angles, but there are no angle forces computed
|
||||
since there was no angle_style command. :dd
|
||||
|
||||
{Atom style in data file differs from currently defined atom style} :dt
|
||||
|
||||
Self-explanatory. :dd
|
||||
@ -73,6 +78,11 @@ short or the bond has blown apart and an atom is too far away. :dd
|
||||
|
||||
Self-explanatory. :dd
|
||||
|
||||
{Bonds are defined but no bond style is set} :dt
|
||||
|
||||
The topology contains bonds, but there are no bond forces computed
|
||||
since there was no bond_style command. :dd
|
||||
|
||||
{Bond/angle/dihedral extent > half of periodic box length} :dt
|
||||
|
||||
This is a restriction because LAMMPS can be confused about which image
|
||||
@ -186,6 +196,11 @@ to check your simulation geometry. :dd
|
||||
|
||||
Self-explanatory. :dd
|
||||
|
||||
{Dihedrals are defined but no dihedral style is set} :dt
|
||||
|
||||
The topology contains dihedrals, but there are no dihedral forces computed
|
||||
since there was no dihedral_style command. :dd
|
||||
|
||||
{Dump dcd/xtc timestamp may be wrong with fix dt/reset} :dt
|
||||
|
||||
If the fix changes the timestep, the dump dcd file will not
|
||||
@ -248,6 +263,10 @@ included one or more of the following: kspace, triclinic, a hybrid
|
||||
pair style, an eam pair style, or no "single" function for the pair
|
||||
style. :dd
|
||||
|
||||
{Fix langevin gjf using random gaussians is not implemented with kokkos} :dt
|
||||
|
||||
This will most likely cause errors in kinetic fluctuations.
|
||||
|
||||
{Fix property/atom mol or charge w/out ghost communication} :dt
|
||||
|
||||
A model typically needs these properties defined for ghost atoms. :dd
|
||||
@ -348,6 +367,11 @@ to check your simulation geometry. :dd
|
||||
|
||||
Self-explanatory. :dd
|
||||
|
||||
{Impropers are defined but no improper style is set} :dt
|
||||
|
||||
The topology contains impropers, but there are no improper forces computed
|
||||
since there was no improper_style command. :dd
|
||||
|
||||
{Inconsistent image flags} :dt
|
||||
|
||||
The image flags for a pair on bonded atoms appear to be inconsistent.
|
||||
@ -403,6 +427,30 @@ This library function cannot be used if atom IDs are not defined or
|
||||
are not consecutively numbered, or if no atom map is defined. See the
|
||||
atom_modify command for details about atom maps. :dd
|
||||
|
||||
{Likewise 1-2 special neighbor interactions != 1.0} :dt
|
||||
|
||||
The topology contains bonds, but there is no bond style defined
|
||||
and a 1-2 special neighbor scaling factor was not 1.0. This
|
||||
means that pair style interactions may have scaled or missing
|
||||
pairs in the neighbor list in expectation of interactions for
|
||||
those pairs being computed from the bond style. :dd
|
||||
|
||||
{Likewise 1-3 special neighbor interactions != 1.0} :dt
|
||||
|
||||
The topology contains angles, but there is no angle style defined
|
||||
and a 1-3 special neighbor scaling factor was not 1.0. This
|
||||
means that pair style interactions may have scaled or missing
|
||||
pairs in the neighbor list in expectation of interactions for
|
||||
those pairs being computed from the angle style. :dd
|
||||
|
||||
{Likewise 1-4 special neighbor interactions != 1.0} :dt
|
||||
|
||||
The topology contains dihedrals, but there is no dihedral style defined
|
||||
and a 1-4 special neighbor scaling factor was not 1.0. This
|
||||
means that pair style interactions may have scaled or missing
|
||||
pairs in the neighbor list in expectation of interactions for
|
||||
those pairs being computed from the dihedral style. :dd
|
||||
|
||||
{Lost atoms via change_box: original %ld current %ld} :dt
|
||||
|
||||
The command options you have used caused atoms to be lost. :dd
|
||||
|
||||
@ -141,6 +141,7 @@ HEAT: compute thermal conductivity for LJ and water via fix ehex
|
||||
KAPPA: compute thermal conductivity via several methods
|
||||
MC: using LAMMPS in a Monte Carlo mode to relax the energy of a system
|
||||
SPIN: examples for features of the SPIN package
|
||||
UNITS: examples that run the same simulation in lj, real, metal units
|
||||
USER: examples for USER packages and USER-contributed commands
|
||||
VISCOSITY: compute viscosity via several methods :tb(s=:)
|
||||
|
||||
|
||||
@ -43,19 +43,19 @@ langevin/spin"_fix_langevin_spin.html. It allows to either dissipate
|
||||
the thermal energy of the Langevin thermostat, or to perform a
|
||||
relaxation of the magnetic configuration toward an equilibrium state.
|
||||
|
||||
The command "fix setforce/spin"_fix_setforce.html allows to set the
|
||||
components of the magnetic precession vectors (while erasing and
|
||||
replacing the previously computed magnetic precession vectors on
|
||||
the atom).
|
||||
This command can be used to freeze the magnetic moment of certain
|
||||
atoms in the simulation by zeroing their precession vector.
|
||||
The command "fix setforce/spin"_fix_setforce.html allows to set the
|
||||
components of the magnetic precession vectors (while erasing and
|
||||
replacing the previously computed magnetic precession vectors on
|
||||
the atom).
|
||||
This command can be used to freeze the magnetic moment of certain
|
||||
atoms in the simulation by zeroing their precession vector.
|
||||
|
||||
The command "fix nve/spin"_fix_nve_spin.html can be used to
|
||||
perform a symplectic integration of the combined dynamics of spins
|
||||
perform a symplectic integration of the combined dynamics of spins
|
||||
and atomic motions.
|
||||
|
||||
The minimization style "min/spin"_min_spin.html can be applied
|
||||
to the spins to perform a minimization of the spin configuration.
|
||||
to the spins to perform a minimization of the spin configuration.
|
||||
|
||||
|
||||
All the computed magnetic properties can be output by two main
|
||||
|
||||
@ -83,7 +83,7 @@ variable d equal $p*$s # dump interval :pre
|
||||
|
||||
# convert from LAMMPS real units to SI :pre
|
||||
|
||||
variable kB equal 1.3806504e-23 # \[J/K/] Boltzmann
|
||||
variable kB equal 1.3806504e-23 # \[J/K\] Boltzmann
|
||||
variable atm2Pa equal 101325.0
|
||||
variable A2m equal 1.0e-10
|
||||
variable fs2s equal 1.0e-15
|
||||
|
||||
BIN
doc/src/JPG/dynamical_matrix_dynmat.jpg
Normal file
|
After Width: | Height: | Size: 17 KiB |
BIN
doc/src/JPG/dynamical_matrix_force_constant.jpg
Normal file
|
After Width: | Height: | Size: 19 KiB |
BIN
doc/src/JPG/dynamical_matrix_phonons.jpg
Normal file
|
After Width: | Height: | Size: 26 KiB |
BIN
doc/src/JPG/third_order_force_constant.png
Normal file
|
After Width: | Height: | Size: 24 KiB |
@ -1,7 +1,7 @@
|
||||
<!-- HTML_ONLY -->
|
||||
<HEAD>
|
||||
<TITLE>LAMMPS Users Manual</TITLE>
|
||||
<META NAME="docnumber" CONTENT="7 Aug 2019 version">
|
||||
<META NAME="docnumber" CONTENT="19 Sep 2019 version">
|
||||
<META NAME="author" CONTENT="http://lammps.sandia.gov - Sandia National Laboratories">
|
||||
<META NAME="copyright" CONTENT="Copyright (2003) Sandia Corporation. This software and manual is distributed under the GNU General Public License.">
|
||||
</HEAD>
|
||||
@ -21,7 +21,7 @@
|
||||
:line
|
||||
|
||||
LAMMPS Documentation :c,h1
|
||||
7 Aug 2019 version :c,h2
|
||||
19 Sep 2019 version :c,h2
|
||||
|
||||
"What is a LAMMPS version?"_Manual_version.html
|
||||
|
||||
|
||||
@ -1746,11 +1746,12 @@ USER-PHONON package :link(PKG-USER-PHONON),h4
|
||||
A "fix phonon"_fix_phonon.html command that calculates dynamical
|
||||
matrices, which can then be used to compute phonon dispersion
|
||||
relations, directly from molecular dynamics simulations.
|
||||
And a "dynamical_matrix" command to compute the dynamical matrix
|
||||
from finite differences.
|
||||
And a "dynamical_matrix"_dynamical_matrix.html as well as a
|
||||
"third_order"_third_order.html command to compute the dynamical matrix
|
||||
and third order tensor from finite differences.
|
||||
|
||||
[Authors:] Ling-Ti Kong (Shanghai Jiao Tong University) for "fix phonon"
|
||||
and Charlie Sievers (UC Davis) for "dynamical_matrix"
|
||||
and Charlie Sievers (UC Davis) for "dynamical_matrix" and "third_order"
|
||||
|
||||
|
||||
[Supporting info:]
|
||||
@ -1759,6 +1760,7 @@ src/USER-PHONON: filenames -> commands
|
||||
src/USER-PHONON/README
|
||||
"fix phonon"_fix_phonon.html
|
||||
"dynamical_matrix"_dynamical_matrix.html
|
||||
"third_order"_third_order.html
|
||||
examples/USER/phonon :ul
|
||||
|
||||
:line
|
||||
|
||||
@ -46,14 +46,14 @@ software version 7.5 or later must be installed on your system. See
|
||||
the discussion for the "GPU package"_Speed_gpu.html for details of how
|
||||
to check and do this.
|
||||
|
||||
NOTE: Kokkos with CUDA currently implicitly assumes that the MPI library
|
||||
is CUDA-aware. This is not always the case, especially when using
|
||||
pre-compiled MPI libraries provided by a Linux distribution. This is not
|
||||
a problem when using only a single GPU with a single MPI rank. When
|
||||
running with multiple MPI ranks, you may see segmentation faults without
|
||||
CUDA-aware MPI support. These can be avoided by adding the flags "-pk
|
||||
kokkos cuda/aware off"_Run_options.html to the LAMMPS command line or by
|
||||
using the command "package kokkos cuda/aware off"_package.html in the
|
||||
NOTE: Kokkos with CUDA currently implicitly assumes that the MPI library
|
||||
is CUDA-aware. This is not always the case, especially when using
|
||||
pre-compiled MPI libraries provided by a Linux distribution. This is not
|
||||
a problem when using only a single GPU with a single MPI rank. When
|
||||
running with multiple MPI ranks, you may see segmentation faults without
|
||||
CUDA-aware MPI support. These can be avoided by adding the flags "-pk
|
||||
kokkos cuda/aware off"_Run_options.html to the LAMMPS command line or by
|
||||
using the command "package kokkos cuda/aware off"_package.html in the
|
||||
input file.
|
||||
|
||||
[Building LAMMPS with the KOKKOS package:]
|
||||
@ -110,10 +110,10 @@ Makefile.kokkos_mpi_only) will give better performance than the OpenMP
|
||||
back end (i.e. Makefile.kokkos_omp) because some of the overhead to make
|
||||
the code thread-safe is removed.
|
||||
|
||||
NOTE: Use the "-pk kokkos" "command-line switch"_Run_options.html to
|
||||
change the default "package kokkos"_package.html options. See its doc
|
||||
page for details and default settings. Experimenting with its options
|
||||
can provide a speed-up for specific calculations. For example:
|
||||
NOTE: Use the "-pk kokkos" "command-line switch"_Run_options.html to
|
||||
change the default "package kokkos"_package.html options. See its doc
|
||||
page for details and default settings. Experimenting with its options
|
||||
can provide a speed-up for specific calculations. For example:
|
||||
|
||||
mpirun -np 16 lmp_kokkos_mpi_only -k on -sf kk -pk kokkos newton on neigh half comm no -in in.lj # Newton on, Half neighbor list, non-threaded comm :pre
|
||||
|
||||
@ -183,15 +183,15 @@ tasks/node. The "-k on t Nt" command-line switch sets the number of
|
||||
threads/task as Nt. The product of these two values should be N, i.e.
|
||||
256 or 264.
|
||||
|
||||
NOTE: The default for the "package kokkos"_package.html command when
|
||||
running on KNL is to use "half" neighbor lists and set the Newton flag
|
||||
to "on" for both pairwise and bonded interactions. This will typically
|
||||
be best for many-body potentials. For simpler pair-wise potentials, it
|
||||
may be faster to use a "full" neighbor list with Newton flag to "off".
|
||||
Use the "-pk kokkos" "command-line switch"_Run_options.html to change
|
||||
the default "package kokkos"_package.html options. See its doc page for
|
||||
details and default settings. Experimenting with its options can provide
|
||||
a speed-up for specific calculations. For example:
|
||||
NOTE: The default for the "package kokkos"_package.html command when
|
||||
running on KNL is to use "half" neighbor lists and set the Newton flag
|
||||
to "on" for both pairwise and bonded interactions. This will typically
|
||||
be best for many-body potentials. For simpler pair-wise potentials, it
|
||||
may be faster to use a "full" neighbor list with Newton flag to "off".
|
||||
Use the "-pk kokkos" "command-line switch"_Run_options.html to change
|
||||
the default "package kokkos"_package.html options. See its doc page for
|
||||
details and default settings. Experimenting with its options can provide
|
||||
a speed-up for specific calculations. For example:
|
||||
|
||||
mpirun -np 64 lmp_kokkos_phi -k on t 4 -sf kk -pk kokkos comm host -in in.reax # Newton on, half neighbor list, threaded comm
|
||||
mpirun -np 64 lmp_kokkos_phi -k on t 4 -sf kk -pk kokkos newton off neigh full comm no -in in.lj # Newton off, full neighbor list, non-threaded comm :pre
|
||||
@ -206,19 +206,19 @@ supports.
|
||||
|
||||
[Running on GPUs:]
|
||||
|
||||
Use the "-k" "command-line switch"_Run_options.html to specify the
|
||||
number of GPUs per node. Typically the -np setting of the mpirun command
|
||||
should set the number of MPI tasks/node to be equal to the number of
|
||||
physical GPUs on the node. You can assign multiple MPI tasks to the same
|
||||
GPU with the KOKKOS package, but this is usually only faster if some
|
||||
portions of the input script have not been ported to use Kokkos. In this
|
||||
case, also packing/unpacking communication buffers on the host may give
|
||||
speedup (see the KOKKOS "package"_package.html command). Using CUDA MPS
|
||||
Use the "-k" "command-line switch"_Run_options.html to specify the
|
||||
number of GPUs per node. Typically the -np setting of the mpirun command
|
||||
should set the number of MPI tasks/node to be equal to the number of
|
||||
physical GPUs on the node. You can assign multiple MPI tasks to the same
|
||||
GPU with the KOKKOS package, but this is usually only faster if some
|
||||
portions of the input script have not been ported to use Kokkos. In this
|
||||
case, also packing/unpacking communication buffers on the host may give
|
||||
speedup (see the KOKKOS "package"_package.html command). Using CUDA MPS
|
||||
is recommended in this scenario.
|
||||
|
||||
Using a CUDA-aware MPI library is highly recommended. CUDA-aware MPI use can be
|
||||
avoided by using "-pk kokkos cuda/aware no"_package.html. As above for
|
||||
multi-core CPUs (and no GPU), if N is the number of physical cores/node,
|
||||
Using a CUDA-aware MPI library is highly recommended. CUDA-aware MPI use can be
|
||||
avoided by using "-pk kokkos cuda/aware no"_package.html. As above for
|
||||
multi-core CPUs (and no GPU), if N is the number of physical cores/node,
|
||||
then the number of MPI tasks/node should not exceed N.
|
||||
|
||||
-k on g Ng :pre
|
||||
@ -229,18 +229,18 @@ one or more nodes, each with two GPUs:
|
||||
mpirun -np 2 lmp_kokkos_cuda_openmpi -k on g 2 -sf kk -in in.lj # 1 node, 2 MPI tasks/node, 2 GPUs/node
|
||||
mpirun -np 32 -ppn 2 lmp_kokkos_cuda_openmpi -k on g 2 -sf kk -in in.lj # 16 nodes, 2 MPI tasks/node, 2 GPUs/node (32 GPUs total) :pre
|
||||
|
||||
NOTE: The default for the "package kokkos"_package.html command when
|
||||
running on GPUs is to use "full" neighbor lists and set the Newton flag
|
||||
to "off" for both pairwise and bonded interactions, along with threaded
|
||||
communication. When running on Maxwell or Kepler GPUs, this will
|
||||
typically be best. For Pascal GPUs, using "half" neighbor lists and
|
||||
setting the Newton flag to "on" may be faster. For many pair styles,
|
||||
setting the neighbor binsize equal to twice the CPU default value will
|
||||
give speedup, which is the default when running on GPUs. Use the "-pk
|
||||
kokkos" "command-line switch"_Run_options.html to change the default
|
||||
"package kokkos"_package.html options. See its doc page for details and
|
||||
default settings. Experimenting with its options can provide a speed-up
|
||||
for specific calculations. For example:
|
||||
NOTE: The default for the "package kokkos"_package.html command when
|
||||
running on GPUs is to use "full" neighbor lists and set the Newton flag
|
||||
to "off" for both pairwise and bonded interactions, along with threaded
|
||||
communication. When running on Maxwell or Kepler GPUs, this will
|
||||
typically be best. For Pascal GPUs, using "half" neighbor lists and
|
||||
setting the Newton flag to "on" may be faster. For many pair styles,
|
||||
setting the neighbor binsize equal to twice the CPU default value will
|
||||
give speedup, which is the default when running on GPUs. Use the "-pk
|
||||
kokkos" "command-line switch"_Run_options.html to change the default
|
||||
"package kokkos"_package.html options. See its doc page for details and
|
||||
default settings. Experimenting with its options can provide a speed-up
|
||||
for specific calculations. For example:
|
||||
|
||||
mpirun -np 2 lmp_kokkos_cuda_openmpi -k on g 2 -sf kk -pk kokkos newton on neigh half binsize 2.8 -in in.lj # Newton on, half neighbor list, set binsize = neighbor ghost cutoff :pre
|
||||
|
||||
|
||||
@ -87,6 +87,7 @@ Miscellaneous tools :h3
|
||||
"emacs"_#emacs,
|
||||
"i-pi"_#ipi,
|
||||
"kate"_#kate,
|
||||
"singularity"_#singularity_tool,
|
||||
"vim"_#vim :tb(c=5,ea=c,a=l)
|
||||
|
||||
:line
|
||||
@ -531,17 +532,26 @@ Ernst Mach Institute in Germany (georg.ganzenmueller at emi.fhg.de).
|
||||
spin tool :h4,link(spin)
|
||||
|
||||
The spin sub-directory contains a C file interpolate.c which can
|
||||
be compiled and used to perform a cubic polynomial interpolation of
|
||||
be compiled and used to perform a cubic polynomial interpolation of
|
||||
the MEP following a GNEB calculation.
|
||||
|
||||
See the README file in tools/spin/interpolate_gneb for more details.
|
||||
|
||||
This tool was written by the SPIN package author, Julien
|
||||
Tranchida at Sandia National Labs (jtranch at sandia.gov, and by Aleksei
|
||||
Tranchida at Sandia National Labs (jtranch at sandia.gov, and by Aleksei
|
||||
Ivanov, at University of Iceland (ali5 at hi.is).
|
||||
|
||||
:line
|
||||
|
||||
singularity tool :h4,link(singularity_tool)
|
||||
|
||||
The singularity sub-directory contains container definitions files
|
||||
that can be used to build container images for building and testing
|
||||
LAMMPS on specific OS variants using the "Singularity"_https://sylabs.io
|
||||
container software. Contributions for additional variants are welcome.
|
||||
|
||||
:line
|
||||
|
||||
vim tool :h4,link(vim)
|
||||
|
||||
The files in the tools/vim directory are add-ons to the VIM editor
|
||||
|
||||
@ -108,6 +108,7 @@ Commands :h1
|
||||
thermo
|
||||
thermo_modify
|
||||
thermo_style
|
||||
third_order
|
||||
timer
|
||||
timestep
|
||||
uncompute
|
||||
|
||||
@ -244,7 +244,7 @@ compute"_Commands_compute.html doc page are followed by one or more of
|
||||
"plasticity/atom"_compute_plasticity_atom.html - Peridynamic plasticity for each atom
|
||||
"pressure"_compute_pressure.html - total pressure and pressure tensor
|
||||
"pressure/cylinder"_compute_pressure_cylinder.html - pressure tensor in cylindrical coordinates
|
||||
"pressure/uef"_compute_pressure_uef.html - pressure tensor in the reference frame of an applied flow field
|
||||
"pressure/uef"_compute_pressure_uef.html - pressure tensor in the reference frame of an applied flow field
|
||||
"property/atom"_compute_property_atom.html - convert atom attributes to per-atom vectors/arrays
|
||||
"property/chunk"_compute_property_chunk.html - extract various per-chunk attributes
|
||||
"property/local"_compute_property_local.html - convert local attributes to localvectors/arrays
|
||||
@ -284,7 +284,7 @@ compute"_Commands_compute.html doc page are followed by one or more of
|
||||
"stress/mop"_compute_stress_mop.html - normal components of the local stress tensor using the method of planes
|
||||
"stress/mop/profile"_compute_stress_mop.html - profile of the normal components of the local stress tensor using the method of planes
|
||||
"stress/tally"_compute_tally.html -
|
||||
"tdpd/cc/atom"_compute_tdpd_cc_atom.html - per-atom chemical concentration of a specified species for each tDPD particle
|
||||
"tdpd/cc/atom"_compute_tdpd_cc_atom.html - per-atom chemical concentration of a specified species for each tDPD particle
|
||||
"temp"_compute_temp.html - temperature of group of atoms
|
||||
"temp/asphere"_compute_temp_asphere.html - temperature of aspherical particles
|
||||
"temp/body"_compute_temp_body.html - temperature of body particles
|
||||
|
||||
@ -47,7 +47,7 @@ neighboring atoms, unless selected by type, type range, or group option,
|
||||
are included in the coordination number tally.
|
||||
|
||||
The optional {group} keyword allows to specify from which group atoms
|
||||
contribute to the coordination number. Default setting is group 'all'.
|
||||
contribute to the coordination number. Default setting is group 'all'.
|
||||
|
||||
The {typeN} keywords allow specification of which atom types
|
||||
contribute to each coordination number. One coordination number is
|
||||
|
||||
@ -84,3 +84,6 @@ package"_Build_package.html doc page for more info.
|
||||
:link(Theodorou)
|
||||
[(Theodorou)] Theodorou, Suter, Macromolecules, 18, 1206 (1985).
|
||||
|
||||
:link(Mattice)
|
||||
[(Mattice)] Mattice, Suter, Conformational Theory of Large Molecules, Wiley, New York, 1994.
|
||||
|
||||
|
||||
@ -34,7 +34,7 @@ compute 2 all hma 1 u cv :pre
|
||||
|
||||
Define a computation that calculates the properties of a solid (potential
|
||||
energy, pressure or heat capacity), using the harmonically-mapped averaging
|
||||
(HMA) method.
|
||||
(HMA) method.
|
||||
This command yields much higher precision than the equivalent compute commands
|
||||
("compute pe"_compute_pe.html, "compute pressure"_compute_pressure.html, etc.)
|
||||
commands during a canonical simulation of an atomic crystal. Specifically,
|
||||
@ -52,7 +52,7 @@ restricted to simulations in the NVT ensemble. While this compute may be
|
||||
used with any potential in LAMMPS, it will provide inaccurate results
|
||||
for potentials that do not go to 0 at the truncation distance;
|
||||
"pair_lj_smooth_linear"_pair_lj_smooth_linear.html and Ewald summation should
|
||||
work fine, while "pair_lj"_pair_lj.html will perform poorly unless
|
||||
work fine, while "pair_lj"_pair_lj.html will perform poorly unless
|
||||
the potential is shifted (via "pair_modify"_pair_modify.html shift) or the cutoff is large. Furthermore, computation of the heat capacity with
|
||||
this compute is restricted to those that implement the single_hessian method
|
||||
in Pair. Implementing single_hessian in additional pair styles is simple.
|
||||
@ -64,8 +64,8 @@ the list of pair styles that currently implement pair_hessian:
|
||||
:ule
|
||||
|
||||
In this method, the analytically known harmonic behavior of a crystal is removed from the traditional ensemble
|
||||
averages, which leads to an accurate and precise measurement of the anharmonic contributions without contamination
|
||||
by noise produced by the already-known harmonic behavior.
|
||||
averages, which leads to an accurate and precise measurement of the anharmonic contributions without contamination
|
||||
by noise produced by the already-known harmonic behavior.
|
||||
A detailed description of this method can be found in ("Moustafa"_#hma-Moustafa). The potential energy is computed by the formula:
|
||||
|
||||
\begin\{equation\}
|
||||
@ -74,9 +74,9 @@ A detailed description of this method can be found in ("Moustafa"_#hma-Moustafa)
|
||||
|
||||
where \(N\) is the number of atoms in the system, \(k_B\) is Boltzmann's
|
||||
constant, \(T\) is the temperature, \(d\) is the
|
||||
dimensionality of the system (2 or 3 for 2d/3d), \(F\bullet\Delta r\) is the sum of dot products of the
|
||||
atomic force vectors and displacement (from lattice sites) vectors, and \(U\) is the sum of
|
||||
pair, bond, angle, dihedral, improper, kspace (long-range), and fix energies.
|
||||
dimensionality of the system (2 or 3 for 2d/3d), \(F\bullet\Delta r\) is the sum of dot products of the
|
||||
atomic force vectors and displacement (from lattice sites) vectors, and \(U\) is the sum of
|
||||
pair, bond, angle, dihedral, improper, kspace (long-range), and fix energies.
|
||||
|
||||
The pressure is computed by the formula:
|
||||
|
||||
@ -118,30 +118,30 @@ When using this keyword, the compute must be first active (it must be included
|
||||
via a "thermo_style custom"_thermo_style.html command) while the atoms are
|
||||
still at their lattice sites (before equilibration).
|
||||
|
||||
The temp-ID specified with compute hma command should be same as the fix-ID of Nose-Hoover ("fix nvt"_fix_nh.html) or
|
||||
Berendsen ("fix temp/berendsen"_fix_temp_berendsen.html) thermostat used for the simulation. While using this command, Langevin thermostat
|
||||
("fix langevin"_fix_langevin.html)
|
||||
should be avoided as its extra forces interfere with the HMA implementation.
|
||||
The temp-ID specified with compute hma command should be same as the fix-ID of Nose-Hoover ("fix nvt"_fix_nh.html) or
|
||||
Berendsen ("fix temp/berendsen"_fix_temp_berendsen.html) thermostat used for the simulation. While using this command, Langevin thermostat
|
||||
("fix langevin"_fix_langevin.html)
|
||||
should be avoided as its extra forces interfere with the HMA implementation.
|
||||
|
||||
|
||||
|
||||
NOTE: Compute hma command should be used right after the energy minimization, when the atoms are at their lattice sites.
|
||||
|
||||
NOTE: Compute hma command should be used right after the energy minimization, when the atoms are at their lattice sites.
|
||||
The simulation should not be started before this command has been used in the input script.
|
||||
|
||||
|
||||
The following example illustrates the placement of this command in the input script:
|
||||
|
||||
|
||||
min_style cg
|
||||
minimize 1e-35 1e-15 50000 500000
|
||||
min_style cg
|
||||
minimize 1e-35 1e-15 50000 500000
|
||||
compute 1 all hma thermostatid u
|
||||
fix thermostatid all nvt temp 600.0 600.0 100.0 :pre
|
||||
fix thermostatid all nvt temp 600.0 600.0 100.0 :pre
|
||||
|
||||
|
||||
|
||||
NOTE: Compute hma should be used when the atoms of the solid do not diffuse. Diffusion will reduce the precision in the potential energy computation.
|
||||
|
||||
|
||||
|
||||
NOTE: The "fix_modify energy yes"_fix_modify.html command must also be specified if a fix is to contribute potential energy to this command.
|
||||
|
||||
An example input script that uses this compute is included in
|
||||
@ -180,5 +180,5 @@ this compute.
|
||||
:line
|
||||
|
||||
:link(hma-Moustafa)
|
||||
[(Moustafa)] Sabry G. Moustafa, Andrew J. Schultz, and David A. Kofke, {Very fast averaging of thermal properties of crystals by molecular simulation},
|
||||
[(Moustafa)] Sabry G. Moustafa, Andrew J. Schultz, and David A. Kofke, {Very fast averaging of thermal properties of crystals by molecular simulation},
|
||||
"Phys. Rev. E \[92\], 043303 (2015)"_https://link.aps.org/doi/10.1103/PhysRevE.92.043303
|
||||
|
||||
@ -76,14 +76,14 @@ parameters up to {Q}12 for a range of commonly encountered
|
||||
high-symmetry structures are given in Table I of "Mickel et
|
||||
al."_#Mickel, and these can be reproduced with this compute
|
||||
|
||||
The optional keyword {wl} will output the third-order invariants {Wl}
|
||||
The optional keyword {wl} will output the third-order invariants {Wl}
|
||||
(see Eq. 1.4 in "Steinhardt"_#Steinhardt) for the same degrees as
|
||||
for the {Ql} parameters. For the FCC crystal with {nnn} =12,
|
||||
{W}4 = -sqrt(14/143).(49/4096)/Pi^1.5 = -0.0006722136...
|
||||
|
||||
The optional keyword {wl/hat} will output the normalized third-order
|
||||
invariants {Wlhat} (see Eq. 2.2 in "Steinhardt"_#Steinhardt)
|
||||
for the same degrees as for the {Ql} parameters. For the FCC crystal
|
||||
The optional keyword {wl/hat} will output the normalized third-order
|
||||
invariants {Wlhat} (see Eq. 2.2 in "Steinhardt"_#Steinhardt)
|
||||
for the same degrees as for the {Ql} parameters. For the FCC crystal
|
||||
with {nnn} =12, {W}4hat = -7/3*sqrt(2/429) = -0.159317...The numerical
|
||||
values of {Wlhat} for a range of commonly encountered high-symmetry
|
||||
structures are given in Table I of "Steinhardt"_#Steinhardt, and these
|
||||
@ -127,9 +127,9 @@ range 0 <= {Ql} <= 1.
|
||||
If the keyword {wl} is set to yes, then the {Wl} values for each
|
||||
atom will be added to the output array, which are real numbers.
|
||||
|
||||
If the keyword {wl/hat} is set to yes, then the {Wl_hat}
|
||||
If the keyword {wl/hat} is set to yes, then the {Wl_hat}
|
||||
values for each atom will be added to the output array, which are real numbers.
|
||||
|
||||
|
||||
If the keyword {components} is set, then the real and imaginary parts
|
||||
of each component of (normalized) {Ybar_lm} will be added to the
|
||||
output array in the following order: Re({Ybar_-m}) Im({Ybar_-m})
|
||||
|
||||
@ -196,7 +196,7 @@ for j1 in range(0,twojmax+1):
|
||||
if (j>=j1): print j1/2.,j2/2.,j/2. :pre
|
||||
|
||||
NOTE: the {diagonal} keyword allowing other possible choices
|
||||
for the number of bispectrum components was removed in 2019,
|
||||
for the number of bispectrum components was removed in 2019,
|
||||
since all potentials use the value of 3, corresponding to the
|
||||
above set of bispectrum components.
|
||||
|
||||
|
||||
@ -40,14 +40,14 @@ The simplest way to output the results of the compute spin calculation
|
||||
is to define some of the quantities as variables, and to use the thermo and
|
||||
thermo_style commands, for example:
|
||||
|
||||
compute out_mag all spin :pre
|
||||
compute out_mag all spin :pre
|
||||
|
||||
variable mag_z equal c_out_mag\[3\]
|
||||
variable mag_norm equal c_out_mag\[4\]
|
||||
variable temp_mag equal c_out_mag\[6\] :pre
|
||||
variable mag_z equal c_out_mag\[3\]
|
||||
variable mag_norm equal c_out_mag\[4\]
|
||||
variable temp_mag equal c_out_mag\[6\] :pre
|
||||
|
||||
thermo 10
|
||||
thermo_style custom step v_mag_z v_mag_norm v_temp_mag :pre
|
||||
thermo 10
|
||||
thermo_style custom step v_mag_z v_mag_norm v_temp_mag :pre
|
||||
|
||||
This series of commands evaluates the total magnetization along z, the norm of
|
||||
the total magnetization, and the magnetic temperature. Three variables are
|
||||
|
||||
@ -23,11 +23,14 @@ style = {many} or {single/bond} or {single/angle} or {single/dihedral} :ule,l
|
||||
btype = bond type of new bond
|
||||
batom1,batom2 = atom IDs for two atoms in bond
|
||||
{single/angle} args = atype aatom1 aatom2 aatom3
|
||||
atype = bond type of new angle
|
||||
atype = angle type of new angle
|
||||
aatom1,aatom2,aatom3 = atom IDs for three atoms in angle
|
||||
{single/dihedral} args = dtype datom1 datom2 datom3 datom4
|
||||
dtype = bond type of new dihedral
|
||||
datom1,datom2,datom3,datom4 = atom IDs for four atoms in dihedral :pre
|
||||
dtype = dihedral type of new dihedral
|
||||
datom1,datom2,datom3,datom4 = atom IDs for four atoms in dihedral
|
||||
{single/improper} args = itype iatom1 iatom2 iatom3 iatom4
|
||||
itype = improper type of new improper
|
||||
iatom1,iatom2,iatom3,iatom4 = atom IDs for four atoms in improper :pre
|
||||
zero or more keyword/value pairs may be appended :l
|
||||
keyword = {special} :l
|
||||
{special} value = {yes} or {no} :pre
|
||||
@ -38,51 +41,54 @@ keyword = {special} :l
|
||||
create_bonds many all all 1 1.0 1.2
|
||||
create_bonds many surf solvent 3 2.0 2.4
|
||||
create_bonds single/bond 1 1 2
|
||||
create_bonds single/angle 5 52 98 107 special no :pre
|
||||
create_bonds single/angle 5 52 98 107 special no
|
||||
create_bonds single/dihedral 2 4 19 27 101
|
||||
create_bonds single/improper 3 23 26 31 57 :pre
|
||||
|
||||
[Description:]
|
||||
|
||||
Create bonds between pairs of atoms that meet a specified distance
|
||||
criteria. Or create a single bond, angle, or dihedral between 2, 3,
|
||||
criteria. Or create a single bond, angle, dihedral or improper between 2, 3,
|
||||
or 4 specified atoms.
|
||||
|
||||
The new bond (angle, dihedral) interactions will then be computed
|
||||
during a simulation by the bond (angle, dihedral) potential defined by
|
||||
The new bond (angle, dihedral, improper) interactions will then be computed
|
||||
during a simulation by the bond (angle, dihedral, improper) potential defined by
|
||||
the "bond_style"_bond_style.html, "bond_coeff"_bond_coeff.html,
|
||||
"angle_style"_angle_style.html, "angle_coeff"_angle_coeff.html,
|
||||
"dihedral_style"_dihedral_style.html,
|
||||
"dihedral_coeff"_dihedral_coeff.html commands.
|
||||
"dihedral_coeff"_dihedral_coeff.html, "improper_style"_improper_style.html,
|
||||
"improper_coeff"_improper_coeff.html commands.
|
||||
|
||||
The {many} style is useful for adding bonds to a system, e.g. between
|
||||
nearest neighbors in a lattice of atoms, without having to enumerate
|
||||
all the bonds in the data file read by the "read_data"_read_data.html
|
||||
command.
|
||||
|
||||
The {single} styles are useful for adding bonds, angles, dihedrals
|
||||
The {single} styles are useful for adding bonds, angles, dihedrals, impropers
|
||||
to a system incrementally, then continuing a simulation.
|
||||
|
||||
Note that this command does not auto-create any angle or dihedral
|
||||
Note that this command does not auto-create any angle, dihedral or improper
|
||||
interactions when a bond is added. Nor does it auto-create any bonds
|
||||
when an angle or dihedral is added. Or auto-create any angles when a
|
||||
dihedral is added. Thus the flexibility of this command is limited.
|
||||
when an angle, dihedral or improper is added. Or auto-create any angles when a
|
||||
dihedral or improper is added. Thus the flexibility of this command is limited.
|
||||
It can be used several times to create different types of bond at
|
||||
different distances. But it cannot typically auto-create all the
|
||||
bonds or angles or dihedral that would normally be defined in a data
|
||||
file for a complex system of molecules.
|
||||
bonds or angles or dihedrals or impropers that would normally be defined in a
|
||||
data file for a complex system of molecules.
|
||||
|
||||
NOTE: If the system has no bonds (angles, dihedrals) to begin with, or
|
||||
if more bonds per atom are being added than currently exist, then you
|
||||
NOTE: If the system has no bonds (angles, dihedrals, impropers) to begin with,
|
||||
or if more bonds per atom are being added than currently exist, then you
|
||||
must insure that the number of bond types and the maximum number of
|
||||
bonds per atom are set to large enough values. And similarly for
|
||||
angles and dihedrals. Otherwise an error may occur when too many
|
||||
bonds (angles, dihedrals) are added to an atom. If the
|
||||
angles, dihedrals and impropers. Otherwise an error may occur when too many
|
||||
bonds (angles, dihedrals, impropers) are added to an atom. If the
|
||||
"read_data"_read_data.html command is used to define the system, these
|
||||
parameters can be set via the "bond types" and "extra bond per atom"
|
||||
fields in the header section of the data file. If the
|
||||
"create_box"_create_box.html command is used to define the system,
|
||||
these 2 parameters can be set via its optional "bond/types" and
|
||||
"extra/bond/per/atom" arguments. And similarly for angles and
|
||||
dihedrals. See the doc pages for these 2 commands for details.
|
||||
"extra/bond/per/atom" arguments. And similarly for angles, dihedrals and
|
||||
impropers. See the doc pages for these 2 commands for details.
|
||||
|
||||
:line
|
||||
|
||||
@ -137,18 +143,25 @@ ordered linearly within the angle; the central atom is {aatom2}.
|
||||
{Atype} must be a value between 1 and the number of angle types
|
||||
defined.
|
||||
|
||||
The {single/dihedral} style creates a single dihedral of type {btype}
|
||||
between two atoms with IDs {batom1} and {batom2}. The ordering of the
|
||||
atoms is the same as in the {Dihedrals} section of a data file read by
|
||||
the "read_data"_read_data.html command. I.e. the 4 atoms are ordered
|
||||
linearly within the dihedral. {Dtype} must be a value between 1 and
|
||||
The {single/dihedral} style creates a single dihedral of type {dtype}
|
||||
between four atoms with IDs {datom1}, {datom2}, {datom3}, and {datom4}. The
|
||||
ordering of the atoms is the same as in the {Dihedrals} section of a data file
|
||||
read by the "read_data"_read_data.html command. I.e. the 4 atoms are ordered
|
||||
linearly within the dihedral. {dtype} must be a value between 1 and
|
||||
the number of dihedral types defined.
|
||||
|
||||
The {single/improper} style creates a single improper of type {itype}
|
||||
between four atoms with IDs {iatom1}, {iatom2}, {iatom3}, and {iatom4}. The
|
||||
ordering of the atoms is the same as in the {Impropers} section of a data file
|
||||
read by the "read_data"_read_data.html command. I.e. the 4 atoms are ordered
|
||||
linearly within the improper. {itype} must be a value between 1 and
|
||||
the number of improper types defined.
|
||||
|
||||
:line
|
||||
|
||||
The keyword {special} controls whether an internal list of special
|
||||
bonds is created after one or more bonds, or a single angle or
|
||||
dihedral is added to the system.
|
||||
bonds is created after one or more bonds, or a single angle, dihedral or
|
||||
improper is added to the system.
|
||||
|
||||
The default value is {yes}. A value of {no} cannot be used
|
||||
with the {many} style.
|
||||
@ -161,16 +174,16 @@ see the "special_bonds"_special_bonds.html command for details.
|
||||
Thus if you are adding a few bonds or a large list of angles all at
|
||||
the same time, by using this command repeatedly, it is more efficient
|
||||
to only trigger the internal list to be created once, after the last
|
||||
bond (or angle, or dihedral) is added:
|
||||
bond (or angle, or dihedral, or improper) is added:
|
||||
|
||||
create_bonds single/bond 5 52 98 special no
|
||||
create_bonds single/bond 5 73 74 special no
|
||||
create_bonds single/bond 5 73 74 special no
|
||||
...
|
||||
create_bonds single/bond 5 17 386 special no
|
||||
create_bonds single/bond 4 112 183 special yes :pre
|
||||
|
||||
Note that you MUST insure the internal list is re-built after the last
|
||||
bond (angle, dihedral) is added, before performing a simulation.
|
||||
bond (angle, dihedral, improper) is added, before performing a simulation.
|
||||
Otherwise pairwise interactions will not be properly excluded or
|
||||
weighted. LAMMPS does NOT check that you have done this correctly.
|
||||
|
||||
|
||||
@ -21,7 +21,8 @@ dump ID group-ID style N file args :pre
|
||||
|
||||
ID = user-assigned name for the dump :ulb,l
|
||||
group-ID = ID of the group of atoms to be dumped :l
|
||||
style = {atom} or {atom/gz} or {atom/mpiio} or {cfg} or {cfg/gz} or {cfg/mpiio} or {custom} or {custom/gz} or {custom/mpiio} or {dcd} or {h5md} or {image} or {local} or {molfile} or {movie} or {netcdf} or {netcdf/mpiio} or {vtk} or {xtc} or {xyz} or {xyz/gz} or {xyz/mpiio} :l
|
||||
style = {atom} or {atom/gz} or {atom/mpiio} or {cfg} or {cfg/gz} or
|
||||
{cfg/mpiio} or {custom} or {custom/gz} or {custom/mpiio} or {dcd} or {h5md} or {image} or {local} or {local/gz} or {molfile} or {movie} or {netcdf} or {netcdf/mpiio} or {vtk} or {xtc} or {xyz} or {xyz/gz} or {xyz/mpiio} :l
|
||||
N = dump every this many timesteps :l
|
||||
file = name of file to write dump info to :l
|
||||
args = list of arguments for a particular style :l
|
||||
|
||||
@ -15,7 +15,7 @@ dump_modify dump-ID keyword values ... :pre
|
||||
dump-ID = ID of dump to modify :ulb,l
|
||||
one or more keyword/value pairs may be appended :l
|
||||
these keywords apply to various dump styles :l
|
||||
keyword = {append} or {at} or {buffer} or {delay} or {element} or {every} or {fileper} or {first} or {flush} or {format} or {image} or {label} or {maxfiles} or {nfile} or {pad} or {precision} or {region} or {scale} or {sort} or {thresh} or {unwrap} :l
|
||||
keyword = {append} or {at} or {buffer} or {delay} or {element} or {every} or {fileper} or {first} or {flush} or {format} or {image} or {label} or {maxfiles} or {nfile} or {pad} or {pbc} or {precision} or {region} or {refresh} or {scale} or {sfactor} or {sort} or {tfactor} or {thermo} or {thresh} or {time} or {units} or {unwrap} :l
|
||||
{append} arg = {yes} or {no}
|
||||
{at} arg = N
|
||||
N = index of frame written upon first dump
|
||||
@ -30,10 +30,10 @@ keyword = {append} or {at} or {buffer} or {delay} or {element} or {every} or {fi
|
||||
{fileper} arg = Np
|
||||
Np = write one file for every this many processors
|
||||
{first} arg = {yes} or {no}
|
||||
{flush} arg = {yes} or {no}
|
||||
{format} args = {line} string, {int} string, {float} string, M string, or {none}
|
||||
string = C-style format string
|
||||
M = integer from 1 to N, where N = # of per-atom quantities being output
|
||||
{flush} arg = {yes} or {no}
|
||||
{image} arg = {yes} or {no}
|
||||
{label} arg = string
|
||||
string = character string (e.g. BONDS) to use in header of dump local file
|
||||
@ -48,18 +48,20 @@ keyword = {append} or {at} or {buffer} or {delay} or {element} or {every} or {fi
|
||||
{refresh} arg = c_ID = compute ID that supports a refresh operation
|
||||
{scale} arg = {yes} or {no}
|
||||
{sfactor} arg = coordinate scaling factor (> 0.0)
|
||||
{thermo} arg = {yes} or {no}
|
||||
{tfactor} arg = time scaling factor (> 0.0)
|
||||
{sort} arg = {off} or {id} or N or -N
|
||||
off = no sorting of per-atom lines within a snapshot
|
||||
id = sort per-atom lines by atom ID
|
||||
N = sort per-atom lines in ascending order by the Nth column
|
||||
-N = sort per-atom lines in descending order by the Nth column
|
||||
{tfactor} arg = time scaling factor (> 0.0)
|
||||
{thermo} arg = {yes} or {no}
|
||||
{time} arg = {yes} or {no}
|
||||
{thresh} args = attribute operator value
|
||||
attribute = same attributes (x,fy,etotal,sxx,etc) used by dump custom style
|
||||
operator = "<" or "<=" or ">" or ">=" or "==" or "!=" or "|^"
|
||||
value = numeric value to compare to, or LAST
|
||||
these 3 args can be replaced by the word "none" to turn off thresholding
|
||||
{units} arg = {yes} or {no}
|
||||
{unwrap} arg = {yes} or {no} :pre
|
||||
these keywords apply only to the {image} and {movie} "styles"_dump_image.html :l
|
||||
keyword = {acolor} or {adiam} or {amap} or {backcolor} or {bcolor} or {bdiam} or {boxcolor} or {color} or {bitrate} or {framerate} :l
|
||||
@ -620,6 +622,37 @@ threshold criterion is met. Otherwise it is not met.
|
||||
|
||||
:line
|
||||
|
||||
The {time} keyword only applies to the dump {atom}, {custom}, and
|
||||
{local} styles (and their COMPRESS package versions {atom/gz},
|
||||
{custom/gz} and {local/gz}). If set to {yes}, each frame will will
|
||||
contain two extra lines before the "ITEM: TIMESTEP" entry:
|
||||
|
||||
ITEM: TIME
|
||||
\<elapsed time\> :pre
|
||||
|
||||
This will output the current elapsed simulation time in current
|
||||
time units equivalent to the "thermo keyword"_thermo_style.html {time}.
|
||||
This is to simplify post-processing of trajectories using a variable time
|
||||
step, e.g. when using "fix dt/reset"_fix_dt_reset.html.
|
||||
The default setting is {no}.
|
||||
|
||||
:line
|
||||
|
||||
The {units} keyword only applies to the dump {atom}, {custom}, and
|
||||
{local} styles (and their COMPRESS package versions {atom/gz},
|
||||
{custom/gz} and {local/gz}). If set to {yes}, each individual dump
|
||||
file will contain two extra lines at the very beginning with:
|
||||
|
||||
ITEM: UNITS
|
||||
\<units style\> :pre
|
||||
|
||||
This will output the current selected "units"_units.html style
|
||||
to the dump file and thus allows visualization and post-processing
|
||||
tools to determine the choice of units of the data in the dump file.
|
||||
The default setting is {no}.
|
||||
|
||||
:line
|
||||
|
||||
The {unwrap} keyword only applies to the dump {dcd} and {xtc} styles.
|
||||
If set to {yes}, coordinates will be written "unwrapped" by the image
|
||||
flags for each atom. Unwrapped means that if the atom has passed through
|
||||
@ -924,6 +957,7 @@ scale = yes
|
||||
sort = off for dump styles {atom}, {custom}, {cfg}, and {local}
|
||||
sort = id for dump styles {dcd}, {xtc}, and {xyz}
|
||||
thresh = none
|
||||
units = no
|
||||
unwrap = no :ul
|
||||
|
||||
acolor = * red/green/blue/yellow/aqua/cyan
|
||||
|
||||
@ -30,14 +30,29 @@ dynamical_matrix 5 eskm 0.00000001 file dynamical.dat binary yes :pre
|
||||
|
||||
[Description:]
|
||||
|
||||
Calculate the dynamical matrix of the selected group.
|
||||
Calculate the dynamical matrix by finite difference of the selected group,
|
||||
|
||||
:c,image(JPG/dynamical_matrix_dynmat.jpg)
|
||||
|
||||
where D is the dynamical matrix and Phi is the force constant matrix defined by
|
||||
|
||||
:c,image(JPG/dynamical_matrix_force_constant.jpg).
|
||||
|
||||
The output for the dynamical matrix is printed three elements at a time. The
|
||||
three elements are the three beta elements for a respective i/alpha/j combination.
|
||||
Each line is printed in order of j increasing first, alpha second, and i last.
|
||||
|
||||
If the style eskm is selected, the dynamical matrix will be in units of inverse squared
|
||||
femtoseconds. These units will then conveniently leave frequencies in THz, where
|
||||
frequencies, represented as omega, can be calculated from
|
||||
|
||||
:c, image(Eqs/dynamical_matrix_phonons.jpg)
|
||||
|
||||
[Restrictions:]
|
||||
|
||||
The command collects the entire dynamical matrix a single MPI rank,
|
||||
so the memory requirements can be very significant for large systems.
|
||||
|
||||
This command assumes a periodic system.
|
||||
The command collects an array of nine times the number of atoms in a group
|
||||
on every single MPI rank, so the memory requirements can be very significant
|
||||
for large systems.
|
||||
|
||||
This command is part of the USER-PHONON package. It is only enabled if
|
||||
LAMMPS was built with that package. See the "Build
|
||||
@ -52,4 +67,4 @@ provided by Pair's single_hessian.
|
||||
|
||||
[Default:]
|
||||
|
||||
The default settings are file = "dynmat.dyn", binary = no
|
||||
The default settings are file = "dynmat.dyn", binary = no
|
||||
|
||||
@ -188,7 +188,7 @@ accelerated styles exist.
|
||||
"box/relax"_fix_box_relax.html - relax box size during energy minimization
|
||||
"client/md"_fix_client_md.html - MD client for client/server simulations
|
||||
"cmap"_fix_cmap.html - enables CMAP cross-terms of the CHARMM force field
|
||||
"colvars"_fix_colvars.html - interface to the collective variables “Colvars” library
|
||||
"colvars"_fix_colvars.html - interface to the collective variables "Colvars" library
|
||||
"controller"_fix_controller.html - apply control loop feedback mechanism
|
||||
"deform"_fix_deform.html - change the simulation box size/shape
|
||||
"deposit"_fix_deposit.html - add new atoms above a surface
|
||||
@ -221,7 +221,7 @@ accelerated styles exist.
|
||||
"heat"_fix_heat.html - add/subtract momentum-conserving heat
|
||||
"hyper/global"_fix_hyper_global.html - global hyperdynamics
|
||||
"hyper/local"_fix_hyper_local.html - local hyperdynamics
|
||||
"imd"_fix_imd.html - implements the “Interactive MD” (IMD) protocol
|
||||
"imd"_fix_imd.html - implements the "Interactive MD" (IMD) protocol
|
||||
"indent"_fix_indent.html - impose force due to an indenter
|
||||
"ipi"_fix_ipi.html - enable LAMMPS to run as a client for i-PI path-integral simulations
|
||||
"langevin"_fix_langevin.html - Langevin temperature control
|
||||
@ -327,7 +327,7 @@ accelerated styles exist.
|
||||
"rigid/nvt/small"_fix_rigid.html - constrain many small clusters of atoms to move as a rigid body with NVT integration
|
||||
"rigid/small"_fix_rigid.html - constrain many small clusters of atoms to move as a rigid body with NVE integration
|
||||
"rx"_fix_rx.html -
|
||||
"saed/vtk"_fix_saed_vtk.html -
|
||||
"saed/vtk"_fix_saed_vtk.html -
|
||||
"setforce"_fix_setforce.html - set the force on each atom
|
||||
"shake"_fix_shake.html - SHAKE constraints on bonds and/or angles
|
||||
"shardlow"_fix_shardlow.html - integration of DPD equations of motion using the Shardlow splitting
|
||||
|
||||
@ -186,20 +186,25 @@ reacting atoms.
|
||||
|
||||
Some atoms in the pre-reacted template that are not reacting may have
|
||||
missing topology with respect to the simulation. For example, the
|
||||
pre-reacted template may contain an atom that would connect to the
|
||||
rest of a long polymer chain. These are referred to as edge atoms, and
|
||||
are also specified in the map file. When the pre-reaction template
|
||||
contains edge atoms, not all atoms, bonds, charges, etc. specified in
|
||||
the reaction templates will be updated. Specifically, topology that
|
||||
involves only atoms that are 'too near' to template edges will not be
|
||||
updated. The definition of 'too near the edge' depends on which
|
||||
interactions are defined in the simulation. If the simulation has
|
||||
defined dihedrals, atoms within two bonds of edge atoms are considered
|
||||
'too near the edge.' If the simulation defines angles, but not
|
||||
dihedrals, atoms within one bond of edge atoms are considered 'too
|
||||
near the edge.' If just bonds are defined, only edge atoms are
|
||||
pre-reacted template may contain an atom that, in the simulation, is
|
||||
currently connected to the rest of a long polymer chain. These are
|
||||
referred to as edge atoms, and are also specified in the map file. All
|
||||
pre-reaction template atoms should be linked to a bonding atom, via at
|
||||
least one path that does not involve edge atoms. When the pre-reaction
|
||||
template contains edge atoms, not all atoms, bonds, charges, etc.
|
||||
specified in the reaction templates will be updated. Specifically,
|
||||
topology that involves only atoms that are 'too near' to template
|
||||
edges will not be updated. The definition of 'too near the edge'
|
||||
depends on which interactions are defined in the simulation. If the
|
||||
simulation has defined dihedrals, atoms within two bonds of edge atoms
|
||||
are considered 'too near the edge.' If the simulation defines angles,
|
||||
but not dihedrals, atoms within one bond of edge atoms are considered
|
||||
'too near the edge.' If just bonds are defined, only edge atoms are
|
||||
considered 'too near the edge.'
|
||||
|
||||
NOTE: Small molecules, i.e. ones that have all their atoms contained
|
||||
within the reaction templates, never have edge atoms.
|
||||
|
||||
Note that some care must be taken when a building a molecule template
|
||||
for a given simulation. All atom types in the pre-reacted template
|
||||
must be the same as those of a potential reaction site in the
|
||||
@ -261,7 +266,7 @@ either 'none' or 'charges.' Further details are provided in the
|
||||
discussion of the 'update_edges' keyword. The fourth optional section
|
||||
begins with the keyword 'Constraints' and lists additional criteria
|
||||
that must be satisfied in order for the reaction to occur. Currently,
|
||||
there is one type of constraint available, as discussed below.
|
||||
there are two types of constraints available, as discussed below.
|
||||
|
||||
A sample map file is given below:
|
||||
|
||||
@ -295,14 +300,23 @@ Equivalences :pre
|
||||
:line
|
||||
|
||||
Any number of additional constraints may be specified in the
|
||||
Constraints section of the map file. Currently there is one type of
|
||||
additional constraint, of type 'distance', whose syntax is as follows:
|
||||
Constraints section of the map file. The constraint of type 'distance'
|
||||
has syntax as follows:
|
||||
|
||||
distance {ID1} {ID2} {rmin} {rmax} :pre
|
||||
|
||||
where 'distance' is the required keyword, {ID1} and {ID2} are
|
||||
pre-reaction atom IDs, and these two atoms must be separated by a
|
||||
distance between {rmin} and {rmax} for the reaction to occur. This
|
||||
distance between {rmin} and {rmax} for the reaction to occur.
|
||||
|
||||
The constraint of type 'angle' has the following syntax:
|
||||
|
||||
angle {ID1} {ID2} {ID3} {amin} {amax} :pre
|
||||
|
||||
where 'angle' is the required keyword, {ID1}, {ID2} and {ID3} are
|
||||
pre-reaction atom IDs, and these three atoms must form an angle
|
||||
between {amin} and {amax} for the reaction to occur (where {ID2} is
|
||||
the central atom). Angles must be specified in degrees. This
|
||||
constraint can be used to enforce a certain orientation between
|
||||
reacting molecules.
|
||||
|
||||
@ -392,10 +406,11 @@ local command.
|
||||
|
||||
[Restart, fix_modify, output, run start/stop, minimize info:]
|
||||
|
||||
No information about this fix is written to "binary restart
|
||||
files"_restart.html, aside from internally-created per-atom
|
||||
properties. None of the "fix_modify"_fix_modify.html options are
|
||||
relevant to this fix.
|
||||
Cumulative reaction counts for each reaction are written to "binary
|
||||
restart files"_restart.html. These values are associated with the
|
||||
reaction name (react-ID). Additionally, internally-created per-atom
|
||||
properties are stored to allow for smooth restarts. None of the
|
||||
"fix_modify"_fix_modify.html options are relevant to this fix.
|
||||
|
||||
This fix computes one statistic for each {react} argument that it
|
||||
stores in a global vector, of length 'number of react arguments', that
|
||||
@ -406,8 +421,8 @@ These is 1 quantity for each react argument:
|
||||
|
||||
(1) cumulative # of reactions occurred :ul
|
||||
|
||||
No parameter of this fix can be used with the {start/stop} keywords of
|
||||
the "run"_run.html command. This fix is not invoked during "energy
|
||||
No parameter of this fix can be used with the {start/stop} keywords
|
||||
of the "run"_run.html command. This fix is not invoked during "energy
|
||||
minimization"_minimize.html.
|
||||
|
||||
When fix bond/react is 'unfixed,' all internally-created groups are
|
||||
@ -417,18 +432,20 @@ all other fixes that use any group created by fix bond/react.
|
||||
[Restrictions:]
|
||||
|
||||
This fix is part of the USER-MISC package. It is only enabled if
|
||||
LAMMPS was built with that package. See the "Build
|
||||
package"_Build_package.html doc page for more info.
|
||||
LAMMPS was built with that package. See the
|
||||
"Build package"_Build_package.html doc page for more info.
|
||||
|
||||
[Related commands:]
|
||||
|
||||
"fix bond/create"_fix_bond_create.html, "fix
|
||||
bond/break"_fix_bond_break.html, "fix bond/swap"_fix_bond_swap.html,
|
||||
"fix bond/create"_fix_bond_create.html,
|
||||
"fix bond/break"_fix_bond_break.html,
|
||||
"fix bond/swap"_fix_bond_swap.html,
|
||||
"dump local"_dump.html, "special_bonds"_special_bonds.html
|
||||
|
||||
[Default:]
|
||||
|
||||
The option defaults are stabilization = no, prob = 1.0, stabilize_steps = 60, update_edges = none
|
||||
The option defaults are stabilization = no, prob = 1.0, stabilize_steps = 60,
|
||||
update_edges = none
|
||||
|
||||
:line
|
||||
|
||||
|
||||
@ -31,7 +31,6 @@ cvar = name of control variable :l
|
||||
|
||||
[Examples:]
|
||||
|
||||
|
||||
fix 1 all controller 100 1.0 0.5 0.0 0.0 c_thermo_temp 1.5 tcontrol
|
||||
fix 1 all controller 100 0.2 0.5 0 100.0 v_pxxwall 1.01325 xwall
|
||||
fix 1 all controller 10000 0.2 0.5 0 2000 v_avpe -3.785 tcontrol :pre
|
||||
|
||||
@ -24,9 +24,10 @@ keyword = {angmom} or {omega} or {scale} or {tally} or {zero} :l
|
||||
{angmom} value = {no} or factor
|
||||
{no} = do not thermostat rotational degrees of freedom via the angular momentum
|
||||
factor = do thermostat rotational degrees of freedom via the angular momentum and apply numeric scale factor as discussed below
|
||||
{gjf} value = {no} or {yes}
|
||||
{gjf} value = {no} or {vfull} or {vhalf}
|
||||
{no} = use standard formulation
|
||||
{yes} = use Gronbech-Jensen/Farago formulation
|
||||
{vfull} = use Gronbech-Jensen/Farago formulation
|
||||
{vhalf} = use 2GJ formulation
|
||||
{omega} value = {no} or {yes}
|
||||
{no} = do not thermostat rotational degrees of freedom via the angular velocity
|
||||
{yes} = do thermostat rotational degrees of freedom via the angular velocity
|
||||
@ -217,6 +218,10 @@ the particles. As described below, this energy can then be printed
|
||||
out or added to the potential energy of the system to monitor energy
|
||||
conservation.
|
||||
|
||||
NOTE: this accumulated energy does NOT include kinetic energy removed
|
||||
by the {zero} flag. LAMMPS will print a warning when both options are
|
||||
active.
|
||||
|
||||
The keyword {zero} can be used to eliminate drift due to the
|
||||
thermostat. Because the random forces on different atoms are
|
||||
independent, they do not sum exactly to zero. As a result, this fix
|
||||
@ -232,29 +237,24 @@ The keyword {gjf} can be used to run the "Gronbech-Jensen/Farago
|
||||
described in the papers cited below, the purpose of this method is to
|
||||
enable longer timesteps to be used (up to the numerical stability
|
||||
limit of the integrator), while still producing the correct Boltzmann
|
||||
distribution of atom positions. It is implemented within LAMMPS, by
|
||||
changing how the random force is applied so that it is composed of
|
||||
the average of two random forces representing half-contributions from
|
||||
the previous and current time intervals.
|
||||
distribution of atom positions.
|
||||
|
||||
In common with all methods based on Verlet integration, the
|
||||
discretized velocities generated by this method in conjunction with
|
||||
velocity-Verlet time integration are not exactly conjugate to the
|
||||
positions. As a result the temperature (computed from the discretized
|
||||
velocities) will be systematically lower than the target temperature,
|
||||
by a small amount which grows with the timestep. Nonetheless, the
|
||||
distribution of atom positions will still be consistent with the
|
||||
The current implementation provides the user with the option to output
|
||||
the velocity in one of two forms: {vfull} or {vhalf}, which replaces
|
||||
the outdated option {yes}. The {gjf} option {vfull} outputs the on-site
|
||||
velocity given in "Gronbech-Jensen/Farago"_#Gronbech-Jensen; this velocity
|
||||
is shown to be systematically lower than the target temperature by a small
|
||||
amount, which grows quadratically with the timestep.
|
||||
The {gjf} option {vhalf} outputs the 2GJ half-step velocity given in
|
||||
"Gronbech Jensen/Gronbech-Jensen"_#2Gronbech-Jensen; for linear systems,
|
||||
this velocity is shown to not have any statistical errors for any stable time step.
|
||||
An overview of statistically correct Boltzmann and Maxwell-Boltzmann
|
||||
sampling of true on-site and true half-step velocities is given in
|
||||
"Gronbech-Jensen"_#1Gronbech-Jensen.
|
||||
Regardless of the choice of output velocity, the sampling of the configurational
|
||||
distribution of atom positions is the same, and linearly consistent with the
|
||||
target temperature.
|
||||
|
||||
As an example of using the {gjf} keyword, for molecules containing C-H
|
||||
bonds, configurational properties generated with dt = 2.5 fs and tdamp
|
||||
= 100 fs are indistinguishable from dt = 0.5 fs. Because the velocity
|
||||
distribution systematically decreases with increasing timestep, the
|
||||
method should not be used to generate properties that depend on the
|
||||
velocity distribution, such as the velocity auto-correlation function
|
||||
(VACF). In this example, the velocity distribution at dt = 2.5fs
|
||||
generates an average temperature of 220 K, instead of 300 K.
|
||||
|
||||
:line
|
||||
|
||||
Styles with a {gpu}, {intel}, {kk}, {omp}, or {opt} suffix are
|
||||
@ -312,7 +312,10 @@ This fix can ramp its target temperature over multiple runs, using the
|
||||
|
||||
This fix is not invoked during "energy minimization"_minimize.html.
|
||||
|
||||
[Restrictions:] none
|
||||
[Restrictions:]
|
||||
|
||||
For {gjf} do not choose damp=dt/2. {gjf} is not compatible
|
||||
with run_style respa.
|
||||
|
||||
[Related commands:]
|
||||
|
||||
@ -335,5 +338,10 @@ types, tally = no, zero = no, gjf = no.
|
||||
|
||||
:link(Gronbech-Jensen)
|
||||
[(Gronbech-Jensen)] Gronbech-Jensen and Farago, Mol Phys, 111, 983
|
||||
(2013); Gronbech-Jensen, Hayre, and Farago, Comp Phys Comm,
|
||||
185, 524 (2014)
|
||||
(2013); Gronbech-Jensen, Hayre, and Farago, Comp Phys Comm, 185, 524 (2014)
|
||||
|
||||
:link(2Gronbech-Jensen)
|
||||
[(Gronbech-Jensen)] Gronbech Jensen and Gronbech-Jensen, Mol Phys, 117, 2511 (2019)
|
||||
|
||||
:link(1Gronbech-Jensen)
|
||||
[(Gronbech-Jensen)] Gronbech-Jensen, Mol Phys (2019); https://doi.org/10.1080/00268976.2019.1662506
|
||||
|
||||
@ -50,7 +50,7 @@ As an example:
|
||||
|
||||
fix 1 all precession/spin zeeman 0.01 0.0 0.0 1.0
|
||||
fix 2 all langevin/spin 300.0 0.01 21
|
||||
fix 3 all nve/spin lattice yes :pre
|
||||
fix 3 all nve/spin lattice moving :pre
|
||||
|
||||
is correct, but defining a force/spin command after the langevin/spin command
|
||||
would give an error message.
|
||||
|
||||
@ -24,18 +24,18 @@ fix 1 active neb/spin 1.0
|
||||
[Description:]
|
||||
|
||||
Add nudging forces to spins in the group for a multi-replica
|
||||
simulation run via the "neb/spin"_neb_spin.html command to perform a
|
||||
geodesic nudged elastic band (GNEB) calculation for finding the
|
||||
simulation run via the "neb/spin"_neb_spin.html command to perform a
|
||||
geodesic nudged elastic band (GNEB) calculation for finding the
|
||||
transition state.
|
||||
Hi-level explanations of GNEB are given with the
|
||||
"neb/spin"_neb_spin.html command and on the
|
||||
"Howto replica"_Howto_replica.html doc page.
|
||||
The fix neb/spin command must be used with the "neb/spin" command and
|
||||
defines how inter-replica nudging forces are computed. A GNEB
|
||||
calculation is divided in two stages. In the first stage n replicas
|
||||
are relaxed toward a MEP until convergence. In the second stage, the
|
||||
climbing image scheme is enabled, so that the replica having the highest
|
||||
energy relaxes toward the saddle point (i.e. the point of highest energy
|
||||
Hi-level explanations of GNEB are given with the
|
||||
"neb/spin"_neb_spin.html command and on the
|
||||
"Howto replica"_Howto_replica.html doc page.
|
||||
The fix neb/spin command must be used with the "neb/spin" command and
|
||||
defines how inter-replica nudging forces are computed. A GNEB
|
||||
calculation is divided in two stages. In the first stage n replicas
|
||||
are relaxed toward a MEP until convergence. In the second stage, the
|
||||
climbing image scheme is enabled, so that the replica having the highest
|
||||
energy relaxes toward the saddle point (i.e. the point of highest energy
|
||||
along the MEP), and a second relaxation is performed.
|
||||
|
||||
The nudging forces are calculated as explained in
|
||||
|
||||
@ -15,22 +15,26 @@ fix ID group-ID nve/spin keyword values :pre
|
||||
ID, group-ID are documented in "fix"_fix.html command :ulb,l
|
||||
nve/spin = style name of this fix command :l
|
||||
keyword = {lattice} :l
|
||||
{lattice} value = {no} or {yes} :pre
|
||||
{lattice} value = {moving} or {frozen}
|
||||
moving = integrate both spin and atomic degress of freedom
|
||||
frozen = integrate spins on a fixed lattice :pre
|
||||
:ule
|
||||
|
||||
[Examples:]
|
||||
|
||||
fix 3 all nve/spin lattice yes
|
||||
fix 1 all nve/spin lattice no :pre
|
||||
fix 3 all nve/spin lattice moving
|
||||
fix 1 all nve/spin lattice frozen :pre
|
||||
|
||||
[Description:]
|
||||
|
||||
Perform a symplectic integration for the spin or spin-lattice system.
|
||||
|
||||
The {lattice} keyword defines if the spins are integrated on a lattice
|
||||
of fixed atoms (lattice = no), or if atoms are moving (lattice = yes).
|
||||
|
||||
By default (lattice = yes), a spin-lattice integration is performed.
|
||||
of fixed atoms (lattice = frozen), or if atoms are moving
|
||||
(lattice = moving).
|
||||
The first case corresponds to a spin dynamics calculation, and
|
||||
the second to a spin-lattice calculation.
|
||||
By default a spin-lattice integration is performed (lattice = moving).
|
||||
|
||||
The {nve/spin} fix applies a Suzuki-Trotter decomposition to
|
||||
the equations of motion of the spin lattice system, following the scheme:
|
||||
@ -63,7 +67,9 @@ instead of "array" is also valid.
|
||||
|
||||
"atom_style spin"_atom_style.html, "fix nve"_fix_nve.html
|
||||
|
||||
[Default:] none
|
||||
[Default:]
|
||||
|
||||
The option default is lattice = moving.
|
||||
|
||||
:line
|
||||
|
||||
|
||||
@ -21,7 +21,7 @@ style = {zeeman} or {anisotropy} or {cubic} :l
|
||||
{anisotropy} args = K x y z
|
||||
K = intensity of the magnetic anisotropy (in eV)
|
||||
x y z = vector direction of the anisotropy :pre
|
||||
{cubic} args = K1 K2c n1x n1y n1x n2x n2y n2z n3x n3y n3z
|
||||
{cubic} args = K1 K2c n1x n1y n1x n2x n2y n2z n3x n3y n3z
|
||||
K1 and K2c = intensity of the magnetic anisotropy (in eV)
|
||||
n1x to n3z = three direction vectors of the cubic anisotropy :pre
|
||||
:ule
|
||||
@ -55,24 +55,24 @@ with n defining the direction of the anisotropy, and K (in eV) its intensity.
|
||||
If K>0, an easy axis is defined, and if K<0, an easy plane is defined.
|
||||
|
||||
Style {cubic} is used to simulate a cubic anisotropy, with three
|
||||
possible easy axis for the magnetic spins in the defined group:
|
||||
possible easy axis for the magnetic spins in the defined group:
|
||||
|
||||
:c,image(Eqs/fix_spin_cubic.jpg)
|
||||
|
||||
with K1 and K2c (in eV) the intensity coefficients and
|
||||
with K1 and K2c (in eV) the intensity coefficients and
|
||||
n1, n2 and n3 defining the three anisotropic directions
|
||||
defined by the command (from n1x to n3z).
|
||||
For n1 = (100), n2 = (010), and n3 = (001), K1 < 0 defines an
|
||||
defined by the command (from n1x to n3z).
|
||||
For n1 = (100), n2 = (010), and n3 = (001), K1 < 0 defines an
|
||||
iron type anisotropy (easy axis along the (001)-type cube
|
||||
edges), and K1 > 0 defines a nickel type anisotropy (easy axis
|
||||
along the (111)-type cube diagonals).
|
||||
along the (111)-type cube diagonals).
|
||||
K2^c > 0 also defines easy axis along the (111)-type cube
|
||||
diagonals.
|
||||
See chapter 2 of "(Skomski)"_#Skomski1 for more details on cubic
|
||||
anisotropies.
|
||||
|
||||
In all cases, the choice of (x y z) only imposes the vector
|
||||
directions for the forces. Only the direction of the vector is
|
||||
directions for the forces. Only the direction of the vector is
|
||||
important; it's length is ignored (the entered vectors are
|
||||
normalized).
|
||||
|
||||
|
||||
@ -44,7 +44,7 @@ fix 1 rods rigid/meso molecule
|
||||
fix 1 spheres rigid/meso single force 1 off off on
|
||||
fix 1 particles rigid/meso molecule force 1*5 off off off force 6*10 off off on
|
||||
fix 2 spheres rigid/meso group 3 sphere1 sphere2 sphere3 torque * off off off :pre
|
||||
|
||||
|
||||
[Description:]
|
||||
|
||||
Treat one or more sets of mesoscopic SPH/SDPD particles as independent
|
||||
|
||||
@ -67,15 +67,15 @@ to it.
|
||||
|
||||
:line
|
||||
|
||||
Style {spin} suffix sets the components of the magnetic precession
|
||||
vectors instead of the mechanical forces. This also erases all
|
||||
previously computed magnetic precession vectors on the atom, though
|
||||
Style {spin} suffix sets the components of the magnetic precession
|
||||
vectors instead of the mechanical forces. This also erases all
|
||||
previously computed magnetic precession vectors on the atom, though
|
||||
additional magnetic fixes could add new forces.
|
||||
|
||||
This command can be used to freeze the magnetic moment of certain
|
||||
atoms in the simulation by zeroing their precession vector.
|
||||
This command can be used to freeze the magnetic moment of certain
|
||||
atoms in the simulation by zeroing their precession vector.
|
||||
|
||||
All options defined above remain valid, they just apply to the magnetic
|
||||
All options defined above remain valid, they just apply to the magnetic
|
||||
precession vectors instead of the forces.
|
||||
|
||||
:line
|
||||
@ -132,7 +132,7 @@ forces to any value besides zero when performing a minimization. Use
|
||||
the "fix addforce"_fix_addforce.html command if you want to apply a
|
||||
non-zero force to atoms during a minimization.
|
||||
|
||||
[Restrictions:]
|
||||
[Restrictions:]
|
||||
|
||||
The fix {setforce/spin} only makes sense when LAMMPS was built with the
|
||||
SPIN package.
|
||||
|
||||
@ -16,7 +16,7 @@ improper_style fourier :pre
|
||||
[Examples:]
|
||||
|
||||
improper_style fourier
|
||||
improper_coeff 1 100.0 180.0 :pre
|
||||
improper_coeff 1 100.0 0.0 1.0 0.5 1 :pre
|
||||
|
||||
[Description:]
|
||||
|
||||
@ -24,12 +24,12 @@ The {fourier} improper style uses the following potential:
|
||||
|
||||
:c,image(Eqs/improper_fourier.jpg)
|
||||
|
||||
where K is the force constant and omega is the angle between the IL
|
||||
axis and the IJK plane:
|
||||
where K is the force constant, C0, C1, C2 are dimensionless coefficients,
|
||||
and omega is the angle between the IL axis and the IJK plane:
|
||||
|
||||
:c,image(JPG/umbrella.jpg)
|
||||
|
||||
If all parameter (see bellow) is not zero, the all the three possible angles will taken in account.
|
||||
If all parameter (see below) is not zero, the all the three possible angles will taken in account.
|
||||
|
||||
The following coefficients must be defined for each improper type via
|
||||
the "improper_coeff"_improper_coeff.html command as in the example
|
||||
@ -38,10 +38,10 @@ above, or in the data file or restart files read by the
|
||||
commands:
|
||||
|
||||
K (energy)
|
||||
C0 (real)
|
||||
C1 (real)
|
||||
C2 (real)
|
||||
all (integer >= 0) :ul
|
||||
C0 (unitless)
|
||||
C1 (unitless)
|
||||
C2 (unitless)
|
||||
all (0 or 1, optional) :ul
|
||||
|
||||
:line
|
||||
|
||||
|
||||
@ -116,10 +116,10 @@ used without a cutoff, i.e. they become full long-range potentials.
|
||||
The {ewald/disp} style can also be used with point-dipoles, see
|
||||
"(Toukmaji)"_#Toukmaji.
|
||||
|
||||
The {ewald/dipole} style adds long-range standard Ewald summations
|
||||
The {ewald/dipole} style adds long-range standard Ewald summations
|
||||
for dipole-dipole interactions, see "(Toukmaji)"_#Toukmaji.
|
||||
|
||||
The {ewald/dipole/spin} style adds long-range standard Ewald
|
||||
The {ewald/dipole/spin} style adds long-range standard Ewald
|
||||
summations for magnetic dipole-dipole interactions between
|
||||
magnetic spins.
|
||||
|
||||
@ -142,11 +142,11 @@ The optional {smallq} argument defines the cutoff for the absolute
|
||||
charge value which determines whether a particle is considered charged
|
||||
or not. Its default value is 1.0e-5.
|
||||
|
||||
The {pppm/dipole} style invokes a particle-particle particle-mesh solver
|
||||
The {pppm/dipole} style invokes a particle-particle particle-mesh solver
|
||||
for dipole-dipole interactions, following the method of "(Cerda)"_#Cerda2008.
|
||||
|
||||
The {pppm/dipole/spin} style invokes a particle-particle particle-mesh solver
|
||||
for magnetic dipole-dipole interactions between magnetic spins.
|
||||
The {pppm/dipole/spin} style invokes a particle-particle particle-mesh solver
|
||||
for magnetic dipole-dipole interactions between magnetic spins.
|
||||
|
||||
The {pppm/tip4p} style is identical to the {pppm} style except that it
|
||||
adds a charge at the massless 4th site in each TIP4P water molecule.
|
||||
|
||||
@ -217,6 +217,7 @@ temper_npt.html
|
||||
thermo.html
|
||||
thermo_modify.html
|
||||
thermo_style.html
|
||||
third_order.html
|
||||
timer.html
|
||||
timestep.html
|
||||
uncompute.html
|
||||
@ -611,6 +612,7 @@ pair_lj_smooth.html
|
||||
pair_lj_smooth_linear.html
|
||||
pair_fep_soft.html
|
||||
pair_lj_switch3_coulgauss.html
|
||||
pair_local_density.html
|
||||
pair_lubricate.html
|
||||
pair_lubricateU.html
|
||||
pair_mdf.html
|
||||
|
||||
@ -13,18 +13,22 @@ min_modify command :h3
|
||||
min_modify keyword values ... :pre
|
||||
|
||||
one or more keyword/value pairs may be listed :ulb,l
|
||||
keyword = {dmax} or {line} or {alpha_damp} or {discrete_factor}
|
||||
keyword = {dmax} or {line} or {norm} or {alpha_damp} or {discrete_factor}
|
||||
{dmax} value = max
|
||||
max = maximum distance for line search to move (distance units)
|
||||
{line} value = {backtrack} or {quadratic} or {forcezero}
|
||||
backtrack,quadratic,forcezero = style of linesearch to use
|
||||
{line} value = {backtrack} or {quadratic} or {forcezero} or {spin_cubic} or {spin_none}
|
||||
backtrack,quadratic,forcezero,spin_cubic,spin_none = style of linesearch to use
|
||||
{norm} value = {two} or {max}
|
||||
two = Euclidean two-norm (length of 3N vector)
|
||||
inf = max force component across all 3-vectors
|
||||
max = max force norm across all 3-vectors
|
||||
{alpha_damp} value = damping
|
||||
damping = fictitious Gilbert damping for spin minimization (adim)
|
||||
{discrete_factor} value = factor
|
||||
factor = discretization factor for adaptive spin timestep (adim) :pre
|
||||
:ule
|
||||
|
||||
these keywords apply only to the "min_style"_min_style.html {adaptglok} :ulb,l
|
||||
these keywords apply only to the "min_style"_min_style.html {fire2} :ulb,l
|
||||
keyword = {integrator} or {tmax} or {tmin} or {delaystep} or {dtgrow} or {dtshrink}
|
||||
or {alpha0} or {alphashrink} or {halfstepback} or {initialdelay} or {vdfmax}
|
||||
{integrator} arg = {eulerimplicit} or {eulerexplicit} or {verlet}
|
||||
@ -95,13 +99,56 @@ difference of two large values (energy before and energy after) and
|
||||
that difference may be smaller than machine epsilon even if atoms
|
||||
could move in the gradient direction to reduce forces further.
|
||||
|
||||
The style {adaptglok} has several parameters that can be tuned in order
|
||||
The choice of a norm can be modified for the min styles {cg}, {sd},
|
||||
{quickmin}, {fire}, {spin}, {spin/cg} and {spin/lbfgs} using
|
||||
the {norm} keyword.
|
||||
The default {two} norm computes the 2-norm (Euclidean length) of the
|
||||
global force vector:
|
||||
|
||||
:c,image(Eqs/norm_two.jpg)
|
||||
|
||||
The {max} norm computes the length of the 3-vector force
|
||||
for each atom (2-norm), and takes the maximum value of those across
|
||||
all atoms
|
||||
|
||||
:c,image(Eqs/norm_max.jpg)
|
||||
|
||||
The {inf} norm takes the maximum component across the forces of
|
||||
all atoms in the system:
|
||||
|
||||
:c,image(Eqs/norm_inf.jpg)
|
||||
|
||||
For the min styles {spin}, {spin/cg} and {spin/lbfgs}, the force
|
||||
norm is replaced by the spin-torque norm.
|
||||
|
||||
Keywords {alpha_damp} and {discrete_factor} only make sense when
|
||||
a "min_spin"_min_spin.html command is declared.
|
||||
Keyword {alpha_damp} defines an analog of a magnetic Gilbert
|
||||
damping. It defines a relaxation rate toward an equilibrium for
|
||||
a given magnetic system.
|
||||
Keyword {discrete_factor} defines a discretization factor for the
|
||||
adaptive timestep used in the {spin} minimization.
|
||||
See "min_spin"_min_spin.html for more information about those
|
||||
quantities.
|
||||
|
||||
The choice of a line search algorithm for the {spin/cg} and
|
||||
{spin/lbfgs} styles can be specified via the {line} keyword.
|
||||
The {spin_cubic} and {spin_none} only make sense when one of those
|
||||
two minimization styles is declared.
|
||||
The {spin_cubic} performs the line search based on a cubic interpolation
|
||||
of the energy along the search direction. The {spin_none} keyword
|
||||
deactivates the line search procedure.
|
||||
The {spin_none} is a default value for {line} keyword for both {spin/lbfgs}
|
||||
and {spin/cg}. Convergence of {spin/lbfgs} can be more robust if
|
||||
{spin_cubic} line search is used.
|
||||
|
||||
The style {fire2} has several parameters that can be tuned in order
|
||||
to optimize the relaxation: {integrator}, {tmax}, {tmin}, {delaystep}, {dtgrow}, {dtshrink},
|
||||
{alpha0}, and {alphashrink}.
|
||||
Different Newton {integrator} can be selected: explicit Euler,
|
||||
semi-implicit Euler (= symplectic Euler) and velocity Verlet.
|
||||
The parameters {tmax} and {tmin} define the maximum and minimum timestep
|
||||
allowed during an adaptglok minimization. Those are not in time unit, but are
|
||||
allowed during an fire2 minimization. Those are not in time unit, but are
|
||||
multiplication factor applied to the "timestep"_timestep.html. Thus
|
||||
{tmax} = 10.0 in metal "units"_units.html means that the maximum value
|
||||
the timestep can be reached during the relaxation is 10 fs (with the default
|
||||
@ -117,18 +164,11 @@ happen when the system comes to be stuck in a local basin of the phase space.
|
||||
For debugging purposes, it is possible to switch off the inertia correction
|
||||
({halfstepback} = {no}) and the initial delay ({initialdelay} = {no}).
|
||||
|
||||
Keywords {alpha_damp} and {discrete_factor} only make sense when
|
||||
a "min_spin"_min_spin.html command is declared.
|
||||
Keyword {alpha_damp} defines an analog of a magnetic Gilbert
|
||||
damping. It defines a relaxation rate toward an equilibrium for
|
||||
a given magnetic system.
|
||||
Keyword {discrete_factor} defines a discretization factor for the
|
||||
adaptive timestep used in the {spin} minimization.
|
||||
See "min_spin"_min_spin.html for more information about those
|
||||
quantities.
|
||||
Default values are {alpha_damp} = 1.0 and {discrete_factor} = 10.0.
|
||||
[Restrictions:]
|
||||
|
||||
[Restrictions:] none
|
||||
For magnetic GNEB calculations, only {spin_none} value for {line} keyword can be used
|
||||
when styles {spin/cg} and {spin/lbfgs} are employed.
|
||||
See "neb/spin"_neb_spin.html for more explanation.
|
||||
|
||||
[Related commands:]
|
||||
|
||||
@ -136,7 +176,13 @@ Default values are {alpha_damp} = 1.0 and {discrete_factor} = 10.0.
|
||||
|
||||
[Default:]
|
||||
|
||||
The option defaults are dmax = 0.1, line = quadratic,
|
||||
The option defaults are dmax = 0.1, line = quadratic and norm = two.
|
||||
|
||||
For the {spin}, {spin/cg} and {spin/lbfgs} styles, the
|
||||
option defaults are alpha_damp = 1.0, discrete_factor = 10.0,
|
||||
line = spin_none, and norm = euclidean.
|
||||
|
||||
For the {fire2} style, the option defaults are
|
||||
integrator = eulerimplicit, tmax = 10.0, tmin = 0.02,
|
||||
delaystep = 20, dtgrow = 1.1, dtshrink = 0.5, alpha0 = 0.25, alphashrink = 0.99,
|
||||
vdfmax = 2000, halfstepback = yes and initialdelay = yes.
|
||||
vdfmax = 2000, halfstepback = yes and initialdelay = yes.
|
||||
@ -6,14 +6,19 @@
|
||||
:line
|
||||
|
||||
min_style spin command :h3
|
||||
min_style spin/cg command :h3
|
||||
min_style spin/lbfgs command :h3
|
||||
|
||||
[Syntax:]
|
||||
|
||||
min_style spin :pre
|
||||
min_style spin
|
||||
min_style spin/cg
|
||||
min_style spin/lbfgs :pre
|
||||
|
||||
[Examples:]
|
||||
|
||||
min_style spin :pre
|
||||
min_style spin/lbfgs
|
||||
min_modify line spin_cubic discrete_factor 10.0 :pre
|
||||
|
||||
[Description:]
|
||||
|
||||
@ -27,28 +32,57 @@ timestep, according to:
|
||||
|
||||
with lambda a damping coefficient (similar to a Gilbert
|
||||
damping).
|
||||
Lambda can be defined by setting the {alpha_damp} keyword with the
|
||||
"min_modify"_min_modify.html command.
|
||||
Lambda can be defined by setting the {alpha_damp} keyword with the
|
||||
"min_modify"_min_modify.html command.
|
||||
|
||||
The minimization procedure solves this equation using an
|
||||
adaptive timestep. The value of this timestep is defined
|
||||
by the largest precession frequency that has to be solved in the
|
||||
adaptive timestep. The value of this timestep is defined
|
||||
by the largest precession frequency that has to be solved in the
|
||||
system:
|
||||
|
||||
:c,image(Eqs/min_spin_timestep.jpg)
|
||||
|
||||
with {|omega|_{max}} the norm of the largest precession frequency
|
||||
in the system (across all processes, and across all replicas if a
|
||||
spin/neb calculation is performed).
|
||||
spin/neb calculation is performed).
|
||||
|
||||
Kappa defines a discretization factor {discrete_factor} for the
|
||||
definition of this timestep.
|
||||
Kappa defines a discretization factor {discrete_factor} for the
|
||||
definition of this timestep.
|
||||
{discrete_factor} can be defined with the "min_modify"_min_modify.html
|
||||
command.
|
||||
|
||||
NOTE: The {spin} style replaces the force tolerance by a torque
|
||||
Style {spin/cg} defines an orthogonal spin optimization
|
||||
(OSO) combined to a conjugate gradient (CG) algorithm.
|
||||
The "min_modify"_min_modify.html command can be used to
|
||||
couple the {spin/cg} to a line search procedure, and to modify the
|
||||
discretization factor {discrete_factor}.
|
||||
By default, style {spin/cg} does not employ the line search procedure
|
||||
and uses the adaptive time-step technique in the same way as style {spin}.
|
||||
|
||||
Style {spin/lbfgs} defines an orthogonal spin optimization
|
||||
(OSO) combined to a limited-memory Broyden-Fletcher-Goldfarb-Shanno
|
||||
(L-BFGS) algorithm.
|
||||
By default, style {spin/lbfgs} does not employ line search procedure.
|
||||
If the line search procedure is not used then the discrete factor defines
|
||||
the maximum root mean squared rotation angle of spins by equation {pi/(5*Kappa)}.
|
||||
The default value for Kappa is 10.
|
||||
The {spin_cubic} line search can improve the convergence of the
|
||||
{spin/lbfgs} algorithm.
|
||||
|
||||
The "min_modify"_min_modify.html command can be used to
|
||||
activate the line search procedure, and to modify the
|
||||
discretization factor {discrete_factor}.
|
||||
|
||||
For more information about styles {spin/cg} and {spin/lbfgs},
|
||||
see their implementation reported in "(Ivanov)"_#Ivanov1.
|
||||
|
||||
NOTE: All the {spin} styles replace the force tolerance by a torque
|
||||
tolerance. See "minimize"_minimize.html for more explanation.
|
||||
|
||||
NOTE: The {spin/cg} and {spin/lbfgs} styles can be used
|
||||
for magnetic NEB calculations only if the line search procedure
|
||||
is deactivated. See "neb/spin"_neb_spin.html for more explanation.
|
||||
|
||||
[Restrictions:]
|
||||
|
||||
This minimization procedure is only applied to spin degrees of
|
||||
@ -56,10 +90,15 @@ freedom for a frozen lattice configuration.
|
||||
|
||||
[Related commands:]
|
||||
|
||||
"min_style"_min_style.html, "minimize"_minimize.html,
|
||||
"min_style"_min_style.html, "minimize"_minimize.html,
|
||||
"min_modify"_min_modify.html
|
||||
|
||||
[Default:]
|
||||
|
||||
The option defaults are {alpha_damp} = 1.0 and {discrete_factor} =
|
||||
10.0.
|
||||
The option defaults are {alpha_damp} = 1.0, {discrete_factor} =
|
||||
10.0, {line} = spin_none and {norm} = euclidean.
|
||||
|
||||
:line
|
||||
|
||||
:link(Ivanov1)
|
||||
[(Ivanov)] Ivanov, Uzdin, Jonsson. arXiv preprint arXiv:1904.02669, (2019).
|
||||
|
||||
@ -11,7 +11,7 @@ min_style command :h3
|
||||
|
||||
min_style style :pre
|
||||
|
||||
style = {cg} or {cg/kk} or {hftn} or {sd} or {quickmin} or {fire} or {spin} or {adaptglok} :ul
|
||||
style = {cg} or {hftn} or {sd} or {quickmin} or {fire} or {fire2} or {spin} or {spin/cg} or {spin/lbfgs} :ul
|
||||
|
||||
[Examples:]
|
||||
|
||||
@ -62,26 +62,40 @@ the velocity non-parallel to the current force vector. The velocity
|
||||
of each atom is initialized to 0.0 by this style, at the beginning of
|
||||
a minimization.
|
||||
|
||||
Style {adaptglok} is a re-implementation of the style {fire} with
|
||||
Style {fire2} is a re-implementation of the style {fire} with
|
||||
additional optimizations of the method described
|
||||
in "(Bitzek)"_#Bitzek, including different time integration schemes.
|
||||
|
||||
Style {spin} is a damped spin dynamics with an adaptive
|
||||
Style {spin} is a damped spin dynamics with an adaptive
|
||||
timestep.
|
||||
See the "min/spin"_min_spin.html doc page for more information.
|
||||
|
||||
Either the {quickmin}, {fire} and {adaptglok} styles are useful in the context of
|
||||
Style {spin/cg} uses an orthogonal spin optimization (OSO)
|
||||
combined to a conjugate gradient (CG) approach to minimize spin
|
||||
configurations.
|
||||
|
||||
Style {spin/lbfgs} uses an orthogonal spin optimization (OSO)
|
||||
combined to a limited-memory Broyden-Fletcher-Goldfarb-Shanno
|
||||
(LBFGS) approach to minimize spin configurations.
|
||||
|
||||
See the "min/spin"_min_spin.html doc page for more information
|
||||
about the {spin}, {spin/cg} and {spin/lbfgs} styles.
|
||||
|
||||
Either the {quickmin}, {fire} and {fire2} styles are useful in the context of
|
||||
nudged elastic band (NEB) calculations via the "neb"_neb.html command.
|
||||
|
||||
Either the {spin}, {spin/cg} and {spin/lbfgs} styles are useful
|
||||
in the context of magnetic geodesic nudged elastic band (GNEB) calculations
|
||||
via the "neb/spin"_neb_spin.html command.
|
||||
|
||||
NOTE: The damped dynamic minimizers use whatever timestep you have
|
||||
defined via the "timestep"_timestep.html command. Often they will
|
||||
converge more quickly if you use a timestep about 10x larger than you
|
||||
would normally use for dynamics simulations.
|
||||
|
||||
NOTE: The {quickmin}, {fire}, {hftn}, and {cg/kk} styles do not yet
|
||||
support the use of the "fix box/relax"_fix_box_relax.html command or
|
||||
minimizations involving the electron radius in "eFF"_pair_eff.html
|
||||
models.
|
||||
NOTE: The {quickmin}, {fire}, {hftn}, and {cg/kk} styles do not yet
|
||||
support the use of the "fix box/relax"_fix_box_relax.html command or
|
||||
minimizations involving the electron radius in "eFF"_pair_eff.html
|
||||
models.
|
||||
|
||||
:line
|
||||
|
||||
|
||||
@ -104,12 +104,13 @@ the line search fails because the step distance backtracks to 0.0
|
||||
the number of outer iterations or timesteps exceeds {maxiter}
|
||||
the number of total force evaluations exceeds {maxeval} :ul
|
||||
|
||||
NOTE: the "minimization style"_min_style.html {spin} replaces
|
||||
NOTE: the "minimization style"_min_style.html {spin},
|
||||
{spin/cg}, and {spin/lbfgs} replace
|
||||
the force tolerance {ftol} by a torque tolerance.
|
||||
The minimization procedure stops if the 2-norm (length) of the
|
||||
global torque vector (defined as the cross product between the
|
||||
spins and their precession vectors omega) is less than {ftol},
|
||||
or if any of the other criteria are met.
|
||||
The minimization procedure stops if the 2-norm (length) of the torque vector on atom
|
||||
(defined as the cross product between the
|
||||
atomic spin and its precession vectors omega) is less than {ftol},
|
||||
or if any of the other criteria are met. Torque have the same units as the energy.
|
||||
|
||||
NOTE: You can also use the "fix halt"_fix_halt.html command to specify
|
||||
a general criterion for exiting a minimization, that is a calculation
|
||||
|
||||
@ -45,7 +45,7 @@ and last are the end points of the transition path.
|
||||
GNEB is a method for finding both the spin configurations and height
|
||||
of the energy barrier associated with a transition state, e.g.
|
||||
spins to perform a collective rotation from one energy basin to
|
||||
another.
|
||||
another.
|
||||
The implementation in LAMMPS follows the discussion in the
|
||||
following paper: "(BessarabA)"_#BessarabA.
|
||||
|
||||
@ -59,35 +59,35 @@ performance speed-up you would see with one or more physical
|
||||
processors per replica. See the "Howto replica"_Howto_replica.html
|
||||
doc page for further discussion.
|
||||
|
||||
NOTE: As explained below, a GNEB calculation performs a damped dynamics
|
||||
minimization across all the replicas. The "spin"_min_spin.html
|
||||
style minimizer has to be defined in your input script.
|
||||
NOTE: As explained below, a GNEB calculation performs a
|
||||
minimization across all the replicas. One of the "spin"_min_spin.html
|
||||
style minimizers has to be defined in your input script.
|
||||
|
||||
When a GNEB calculation is performed, it is assumed that each replica
|
||||
is running the same system, though LAMMPS does not check for this.
|
||||
I.e. the simulation domain, the number of magnetic atoms, the
|
||||
interaction potentials, and the starting configuration when the neb
|
||||
I.e. the simulation domain, the number of magnetic atoms, the
|
||||
interaction potentials, and the starting configuration when the neb
|
||||
command is issued should be the same for every replica.
|
||||
|
||||
In a GNEB calculation each replica is connected to other replicas by
|
||||
inter-replica nudging forces. These forces are imposed by the "fix
|
||||
neb/spin"_fix_neb_spin.html command, which must be used in conjunction
|
||||
with the neb command.
|
||||
neb/spin"_fix_neb_spin.html command, which must be used in conjunction
|
||||
with the neb command.
|
||||
The group used to define the fix neb/spin command defines the
|
||||
GNEB magnetic atoms which are the only ones that inter-replica springs
|
||||
are applied to.
|
||||
GNEB magnetic atoms which are the only ones that inter-replica springs
|
||||
are applied to.
|
||||
If the group does not include all magnetic atoms, then non-GNEB
|
||||
magnetic atoms have no inter-replica springs and the torques they feel
|
||||
and their precession motion is computed in the usual way due only
|
||||
to other magnetic atoms within their replica.
|
||||
Conceptually, the non-GNEB atoms provide a background force field for
|
||||
the GNEB atoms.
|
||||
Their magnetic spins can be allowed to evolve during the GNEB
|
||||
magnetic atoms have no inter-replica springs and the torques they feel
|
||||
and their precession motion is computed in the usual way due only
|
||||
to other magnetic atoms within their replica.
|
||||
Conceptually, the non-GNEB atoms provide a background force field for
|
||||
the GNEB atoms.
|
||||
Their magnetic spins can be allowed to evolve during the GNEB
|
||||
minimization procedure.
|
||||
|
||||
The initial spin configuration for each of the replicas can be
|
||||
specified in different manners via the {file-style} setting, as
|
||||
discussed below. Only atomic spins whose initial coordinates should
|
||||
discussed below. Only atomic spins whose initial coordinates should
|
||||
differ from the current configuration need to be specified.
|
||||
|
||||
Conceptually, the initial and final configurations for the first
|
||||
@ -106,21 +106,21 @@ closer to the MEP and read them in.
|
||||
:line
|
||||
|
||||
For a {file-style} setting of {final}, a filename is specified which
|
||||
contains atomic and spin coordinates for zero or more atoms, in the
|
||||
format described below.
|
||||
For each atom that appears in the file, the new coordinates are
|
||||
assigned to that atom in the final replica. Each intermediate replica
|
||||
also assigns a new spin to that atom in an interpolated manner.
|
||||
This is done by using the current direction of the spin at the starting
|
||||
point and the read-in direction as the final point.
|
||||
The "angular distance" between them is calculated, and the new direction
|
||||
contains atomic and spin coordinates for zero or more atoms, in the
|
||||
format described below.
|
||||
For each atom that appears in the file, the new coordinates are
|
||||
assigned to that atom in the final replica. Each intermediate replica
|
||||
also assigns a new spin to that atom in an interpolated manner.
|
||||
This is done by using the current direction of the spin at the starting
|
||||
point and the read-in direction as the final point.
|
||||
The "angular distance" between them is calculated, and the new direction
|
||||
is assigned to be a fraction of the angular distance.
|
||||
|
||||
NOTE: The "angular distance" between the starting and final point is
|
||||
evaluated in the geodesic sense, as described in
|
||||
"(BessarabA)"_#BessarabA.
|
||||
NOTE: The "angular distance" between the starting and final point is
|
||||
evaluated in the geodesic sense, as described in
|
||||
"(BessarabA)"_#BessarabA.
|
||||
|
||||
NOTE: The angular interpolation between the starting and final point
|
||||
NOTE: The angular interpolation between the starting and final point
|
||||
is achieved using Rodrigues formula:
|
||||
|
||||
:c,image(Eqs/neb_spin_rodrigues_formula.jpg)
|
||||
@ -130,7 +130,7 @@ omega_i^nu is a rotation angle defined as:
|
||||
|
||||
:c,image(Eqs/neb_spin_angle.jpg)
|
||||
|
||||
with nu the image number, Q the total number of images, and
|
||||
with nu the image number, Q the total number of images, and
|
||||
omega_i the total rotation between the initial and final spins.
|
||||
k_i defines a rotation axis such as:
|
||||
|
||||
@ -139,16 +139,16 @@ k_i defines a rotation axis such as:
|
||||
if the initial and final spins are not aligned.
|
||||
If the initial and final spins are aligned, then their cross
|
||||
product is null, and the expression above does not apply.
|
||||
If they point toward the same direction, the intermediate images
|
||||
If they point toward the same direction, the intermediate images
|
||||
conserve the same orientation.
|
||||
If the initial and final spins are aligned, but point toward
|
||||
opposite directions, an arbitrary rotation vector belonging to
|
||||
the plane perpendicular to initial and final spins is chosen.
|
||||
the plane perpendicular to initial and final spins is chosen.
|
||||
In this case, a warning message is displayed.
|
||||
|
||||
For a {file-style} setting of {each}, a filename is specified which is
|
||||
assumed to be unique to each replica.
|
||||
See the "neb"_neb.html documentation page for more information about this
|
||||
assumed to be unique to each replica.
|
||||
See the "neb"_neb.html documentation page for more information about this
|
||||
option.
|
||||
|
||||
For a {file-style} setting of {none}, no filename is specified. Each
|
||||
@ -170,9 +170,10 @@ command is issued.
|
||||
:line
|
||||
|
||||
A NEB calculation proceeds in two stages, each of which is a
|
||||
minimization procedure, performed via damped dynamics. To enable
|
||||
this, you must first define a damped spin dynamics
|
||||
"min_style"_min_style.html, using the {spin} style (see
|
||||
minimization procedure. To enable
|
||||
this, you must first define a
|
||||
"min_style"_min_style.html, using either the {spin},
|
||||
{spin/cg}, or {spin/lbfgs} style (see
|
||||
"min_spin"_min_spin.html for more information).
|
||||
The other styles cannot be used, since they relax the lattice
|
||||
degrees of freedom instead of the spins.
|
||||
@ -195,9 +196,9 @@ damped dynamics is like a single timestep in a dynamics
|
||||
replica and its normalized distance along the reaction path (reaction
|
||||
coordinate RD) will be printed to the screen and log file every
|
||||
{Nevery} timesteps. The RD is 0 and 1 for the first and last replica.
|
||||
For intermediate replicas, it is the cumulative angular distance
|
||||
(normalized by the total cumulative angular distance) between adjacent
|
||||
replicas, where "distance" is defined as the length of the 3N-vector of
|
||||
For intermediate replicas, it is the cumulative angular distance
|
||||
(normalized by the total cumulative angular distance) between adjacent
|
||||
replicas, where "distance" is defined as the length of the 3N-vector of
|
||||
the geodesic distances in spin coordinates, with N the number of
|
||||
GNEB spins involved (see equation (13) in "(BessarabA)"_#BessarabA).
|
||||
These outputs allow you to monitor NEB's progress in
|
||||
@ -207,11 +208,11 @@ of {Nevery}.
|
||||
In the first stage of GNEB, the set of replicas should converge toward
|
||||
a minimum energy path (MEP) of conformational states that transition
|
||||
over a barrier. The MEP for a transition is defined as a sequence of
|
||||
3N-dimensional spin states, each of which has a potential energy
|
||||
gradient parallel to the MEP itself.
|
||||
The configuration of highest energy along a MEP corresponds to a saddle
|
||||
point. The replica states will also be roughly equally spaced along
|
||||
the MEP due to the inter-replica nudging force added by the
|
||||
3N-dimensional spin states, each of which has a potential energy
|
||||
gradient parallel to the MEP itself.
|
||||
The configuration of highest energy along a MEP corresponds to a saddle
|
||||
point. The replica states will also be roughly equally spaced along
|
||||
the MEP due to the inter-replica nudging force added by the
|
||||
"fix neb"_fix_neb.html command.
|
||||
|
||||
In the second stage of GNEB, the replica with the highest energy is
|
||||
@ -234,12 +235,12 @@ An atom map must be defined which it is not by default for "atom_style
|
||||
atomic"_atom_style.html problems. The "atom_modify
|
||||
map"_atom_modify.html command can be used to do this.
|
||||
|
||||
An initial value can be defined for the timestep. Although, the {spin}
|
||||
minimization algorithm is an adaptive timestep methodology, so that
|
||||
this timestep is likely to evolve during the calculation.
|
||||
An initial value can be defined for the timestep. Although, the {spin}
|
||||
minimization algorithm is an adaptive timestep methodology, so that
|
||||
this timestep is likely to evolve during the calculation.
|
||||
|
||||
The minimizers in LAMMPS operate on all spins in your system, even
|
||||
non-GNEB atoms, as defined above.
|
||||
non-GNEB atoms, as defined above.
|
||||
|
||||
:line
|
||||
|
||||
@ -257,7 +258,7 @@ ID2 g2 x2 y2 z2 sx2 sy2 sz2
|
||||
...
|
||||
IDN gN yN zN sxN syN szN :pre
|
||||
|
||||
The fields are the atom ID, the norm of the associated magnetic spin,
|
||||
The fields are the atom ID, the norm of the associated magnetic spin,
|
||||
followed by the {x,y,z} coordinates and the {sx,sy,sz} spin coordinates.
|
||||
The lines can be listed in any order. Additional trailing information on
|
||||
the line is OK, such as a comment.
|
||||
@ -290,22 +291,22 @@ reaction coordinate and potential energy of each replica.
|
||||
|
||||
The "maximum torque per replica" is the two-norm of the
|
||||
3N-length vector given by the cross product of a spin by its
|
||||
precession vector omega, in each replica, maximized across replicas,
|
||||
precession vector omega, in each replica, maximized across replicas,
|
||||
which is what the {ttol} setting is checking against. In this case, N is
|
||||
all the atoms in each replica. The "maximum torque per atom" is the
|
||||
maximum torque component of any atom in any replica. The potential
|
||||
gradients are the two-norm of the 3N-length magnetic precession vector
|
||||
solely due to the interaction potential i.e. without adding in
|
||||
inter-replica forces, and projected along the path tangent (as detailed
|
||||
gradients are the two-norm of the 3N-length magnetic precession vector
|
||||
solely due to the interaction potential i.e. without adding in
|
||||
inter-replica forces, and projected along the path tangent (as detailed
|
||||
in Appendix D of "(BessarabA)"_#BessarabA).
|
||||
|
||||
The "reaction coordinate" (RD) for each replica is the two-norm of the
|
||||
3N-length vector of geodesic distances between its spins and the preceding
|
||||
replica's spins (see equation (13) of "(BessarabA)"_#BessarabA), added to
|
||||
the RD of the preceding replica. The RD of the first replica RD1 = 0.0;
|
||||
the RD of the final replica RDN = RDT, the total reaction coordinate.
|
||||
The normalized RDs are divided by RDT, so that they form a monotonically
|
||||
increasing sequence from zero to one. When computing RD, N only includes
|
||||
replica's spins (see equation (13) of "(BessarabA)"_#BessarabA), added to
|
||||
the RD of the preceding replica. The RD of the first replica RD1 = 0.0;
|
||||
the RD of the final replica RDN = RDT, the total reaction coordinate.
|
||||
The normalized RDs are divided by RDT, so that they form a monotonically
|
||||
increasing sequence from zero to one. When computing RD, N only includes
|
||||
the spins being operated on by the fix neb/spin command.
|
||||
|
||||
The forward (reverse) energy barrier is the potential energy of the
|
||||
@ -313,17 +314,17 @@ highest replica minus the energy of the first (last) replica.
|
||||
|
||||
Supplementary information for all replicas can be printed out to the
|
||||
screen and master log.lammps file by adding the verbose keyword. This
|
||||
information include the following.
|
||||
The "GradVidottan" are the projections of the potential gradient for
|
||||
the replica i on its tangent vector (as detailed in Appendix D of
|
||||
information include the following.
|
||||
The "GradVidottan" are the projections of the potential gradient for
|
||||
the replica i on its tangent vector (as detailed in Appendix D of
|
||||
"(BessarabA)"_#BessarabA).
|
||||
The "DNi" are the non normalized geodesic distances (see equation (13)
|
||||
of "(BessarabA)"_#BessarabA), between a replica i and the next replica
|
||||
The "DNi" are the non normalized geodesic distances (see equation (13)
|
||||
of "(BessarabA)"_#BessarabA), between a replica i and the next replica
|
||||
i+1. For the last replica, this distance is not defined and a "NAN"
|
||||
value is the corresponding output.
|
||||
value is the corresponding output.
|
||||
|
||||
When a NEB calculation does not converge properly, the supplementary
|
||||
information can help understanding what is going wrong.
|
||||
information can help understanding what is going wrong.
|
||||
|
||||
When running on multiple partitions, LAMMPS produces additional log
|
||||
files for each partition, e.g. log.lammps.0, log.lammps.1, etc. For a
|
||||
@ -346,9 +347,9 @@ restart the calculation from an intermediate point with altered
|
||||
parameters.
|
||||
|
||||
A c file script in provided in the tool/spin/interpolate_gneb
|
||||
directory, that interpolates the MEP given the information provided
|
||||
directory, that interpolates the MEP given the information provided
|
||||
by the verbose output option (as detailed in Appendix D of
|
||||
"(BessarabA)"_#BessarabA).
|
||||
"(BessarabA)"_#BessarabA).
|
||||
|
||||
:line
|
||||
|
||||
@ -358,6 +359,9 @@ This command can only be used if LAMMPS was built with the SPIN
|
||||
package. See the "Build package"_Build_package.html doc
|
||||
page for more info.
|
||||
|
||||
For magnetic GNEB calculations, only {spin_none} value for {line} keyword can be used
|
||||
when styles {spin/cg} and {spin/lbfgs} are employed.
|
||||
|
||||
:line
|
||||
|
||||
[Related commands:]
|
||||
|
||||
@ -423,115 +423,115 @@ processes/threads used for LAMMPS.
|
||||
|
||||
:line
|
||||
|
||||
The {kokkos} style invokes settings associated with the use of the
|
||||
KOKKOS package.
|
||||
The {kokkos} style invokes settings associated with the use of the
|
||||
KOKKOS package.
|
||||
|
||||
All of the settings are optional keyword/value pairs. Each has a default
|
||||
value as listed below.
|
||||
All of the settings are optional keyword/value pairs. Each has a default
|
||||
value as listed below.
|
||||
|
||||
The {neigh} keyword determines how neighbor lists are built. A value of
|
||||
{half} uses a thread-safe variant of half-neighbor lists, the same as
|
||||
used by most pair styles in LAMMPS, which is the default when running on
|
||||
CPUs (i.e. the Kokkos CUDA back end is not enabled).
|
||||
The {neigh} keyword determines how neighbor lists are built. A value of
|
||||
{half} uses a thread-safe variant of half-neighbor lists, the same as
|
||||
used by most pair styles in LAMMPS, which is the default when running on
|
||||
CPUs (i.e. the Kokkos CUDA back end is not enabled).
|
||||
|
||||
A value of {full} uses a full neighbor lists and is the default when
|
||||
running on GPUs. This performs twice as much computation as the {half}
|
||||
option, however that is often a win because it is thread-safe and
|
||||
doesn't require atomic operations in the calculation of pair forces. For
|
||||
that reason, {full} is the default setting for GPUs. However, when
|
||||
running on CPUs, a {half} neighbor list is the default because it are
|
||||
often faster, just as it is for non-accelerated pair styles. Similarly,
|
||||
the {neigh/qeq} keyword determines how neighbor lists are built for "fix
|
||||
qeq/reax/kk"_fix_qeq_reax.html. If not explicitly set, the value of
|
||||
A value of {full} uses a full neighbor lists and is the default when
|
||||
running on GPUs. This performs twice as much computation as the {half}
|
||||
option, however that is often a win because it is thread-safe and
|
||||
doesn't require atomic operations in the calculation of pair forces. For
|
||||
that reason, {full} is the default setting for GPUs. However, when
|
||||
running on CPUs, a {half} neighbor list is the default because it are
|
||||
often faster, just as it is for non-accelerated pair styles. Similarly,
|
||||
the {neigh/qeq} keyword determines how neighbor lists are built for "fix
|
||||
qeq/reax/kk"_fix_qeq_reax.html. If not explicitly set, the value of
|
||||
{neigh/qeq} will match {neigh}.
|
||||
|
||||
If the {neigh/thread} keyword is set to {off}, then the KOKKOS package
|
||||
threads only over atoms. However, for small systems, this may not expose
|
||||
enough parallelism to keep a GPU busy. When this keyword is set to {on},
|
||||
the KOKKOS package threads over both atoms and neighbors of atoms. When
|
||||
using {neigh/thread} {on}, a full neighbor list must also be used. Using
|
||||
{neigh/thread} {on} may be slower for large systems, so this this option
|
||||
is turned on by default only when there are 16K atoms or less owned by
|
||||
an MPI rank and when using a full neighbor list. Not all KOKKOS-enabled
|
||||
potentials support this keyword yet, and only thread over atoms. Many
|
||||
simple pair-wise potentials such as Lennard-Jones do support threading
|
||||
If the {neigh/thread} keyword is set to {off}, then the KOKKOS package
|
||||
threads only over atoms. However, for small systems, this may not expose
|
||||
enough parallelism to keep a GPU busy. When this keyword is set to {on},
|
||||
the KOKKOS package threads over both atoms and neighbors of atoms. When
|
||||
using {neigh/thread} {on}, a full neighbor list must also be used. Using
|
||||
{neigh/thread} {on} may be slower for large systems, so this this option
|
||||
is turned on by default only when there are 16K atoms or less owned by
|
||||
an MPI rank and when using a full neighbor list. Not all KOKKOS-enabled
|
||||
potentials support this keyword yet, and only thread over atoms. Many
|
||||
simple pair-wise potentials such as Lennard-Jones do support threading
|
||||
over both atoms and neighbors.
|
||||
|
||||
The {newton} keyword sets the Newton flags for pairwise and bonded
|
||||
interactions to {off} or {on}, the same as the "newton"_newton.html
|
||||
command allows. The default for GPUs is {off} because this will almost
|
||||
always give better performance for the KOKKOS package. This means more
|
||||
computation is done, but less communication. However, when running on
|
||||
CPUs a value of {on} is the default since it can often be faster, just
|
||||
as it is for non-accelerated pair styles
|
||||
The {newton} keyword sets the Newton flags for pairwise and bonded
|
||||
interactions to {off} or {on}, the same as the "newton"_newton.html
|
||||
command allows. The default for GPUs is {off} because this will almost
|
||||
always give better performance for the KOKKOS package. This means more
|
||||
computation is done, but less communication. However, when running on
|
||||
CPUs a value of {on} is the default since it can often be faster, just
|
||||
as it is for non-accelerated pair styles
|
||||
|
||||
The {binsize} keyword sets the size of bins used to bin atoms in
|
||||
neighbor list builds. The same value can be set by the "neigh_modify
|
||||
binsize"_neigh_modify.html command. Making it an option in the package
|
||||
kokkos command allows it to be set from the command line. The default
|
||||
value for CPUs is 0.0, which means the LAMMPS default will be used,
|
||||
which is bins = 1/2 the size of the pairwise cutoff + neighbor skin
|
||||
distance. This is fine when neighbor lists are built on the CPU. For GPU
|
||||
builds, a 2x larger binsize equal to the pairwise cutoff + neighbor skin
|
||||
is often faster, which is the default. Note that if you use a
|
||||
longer-than-usual pairwise cutoff, e.g. to allow for a smaller fraction
|
||||
of KSpace work with a "long-range Coulombic solver"_kspace_style.html
|
||||
because the GPU is faster at performing pairwise interactions, then this
|
||||
rule of thumb may give too large a binsize and the default should be
|
||||
overridden with a smaller value.
|
||||
The {binsize} keyword sets the size of bins used to bin atoms in
|
||||
neighbor list builds. The same value can be set by the "neigh_modify
|
||||
binsize"_neigh_modify.html command. Making it an option in the package
|
||||
kokkos command allows it to be set from the command line. The default
|
||||
value for CPUs is 0.0, which means the LAMMPS default will be used,
|
||||
which is bins = 1/2 the size of the pairwise cutoff + neighbor skin
|
||||
distance. This is fine when neighbor lists are built on the CPU. For GPU
|
||||
builds, a 2x larger binsize equal to the pairwise cutoff + neighbor skin
|
||||
is often faster, which is the default. Note that if you use a
|
||||
longer-than-usual pairwise cutoff, e.g. to allow for a smaller fraction
|
||||
of KSpace work with a "long-range Coulombic solver"_kspace_style.html
|
||||
because the GPU is faster at performing pairwise interactions, then this
|
||||
rule of thumb may give too large a binsize and the default should be
|
||||
overridden with a smaller value.
|
||||
|
||||
The {comm} and {comm/exchange} and {comm/forward} and {comm/reverse}
|
||||
keywords determine whether the host or device performs the packing and
|
||||
unpacking of data when communicating per-atom data between processors.
|
||||
"Exchange" communication happens only on timesteps that neighbor lists
|
||||
are rebuilt. The data is only for atoms that migrate to new processors.
|
||||
"Forward" communication happens every timestep. "Reverse" communication
|
||||
happens every timestep if the {newton} option is on. The data is for
|
||||
atom coordinates and any other atom properties that needs to be updated
|
||||
The {comm} and {comm/exchange} and {comm/forward} and {comm/reverse}
|
||||
keywords determine whether the host or device performs the packing and
|
||||
unpacking of data when communicating per-atom data between processors.
|
||||
"Exchange" communication happens only on timesteps that neighbor lists
|
||||
are rebuilt. The data is only for atoms that migrate to new processors.
|
||||
"Forward" communication happens every timestep. "Reverse" communication
|
||||
happens every timestep if the {newton} option is on. The data is for
|
||||
atom coordinates and any other atom properties that needs to be updated
|
||||
for ghost atoms owned by each processor.
|
||||
|
||||
The {comm} keyword is simply a short-cut to set the same value for both
|
||||
The {comm} keyword is simply a short-cut to set the same value for both
|
||||
the {comm/exchange} and {comm/forward} and {comm/reverse} keywords.
|
||||
|
||||
The value options for all 3 keywords are {no} or {host} or {device}. A
|
||||
value of {no} means to use the standard non-KOKKOS method of
|
||||
packing/unpacking data for the communication. A value of {host} means to
|
||||
use the host, typically a multi-core CPU, and perform the
|
||||
packing/unpacking in parallel with threads. A value of {device} means to
|
||||
use the device, typically a GPU, to perform the packing/unpacking
|
||||
The value options for all 3 keywords are {no} or {host} or {device}. A
|
||||
value of {no} means to use the standard non-KOKKOS method of
|
||||
packing/unpacking data for the communication. A value of {host} means to
|
||||
use the host, typically a multi-core CPU, and perform the
|
||||
packing/unpacking in parallel with threads. A value of {device} means to
|
||||
use the device, typically a GPU, to perform the packing/unpacking
|
||||
operation.
|
||||
|
||||
The optimal choice for these keywords depends on the input script and
|
||||
the hardware used. The {no} value is useful for verifying that the
|
||||
Kokkos-based {host} and {device} values are working correctly. It is the
|
||||
The optimal choice for these keywords depends on the input script and
|
||||
the hardware used. The {no} value is useful for verifying that the
|
||||
Kokkos-based {host} and {device} values are working correctly. It is the
|
||||
default when running on CPUs since it is usually the fastest.
|
||||
|
||||
When running on CPUs or Xeon Phi, the {host} and {device} values work
|
||||
identically. When using GPUs, the {device} value is the default since it
|
||||
will typically be optimal if all of your styles used in your input
|
||||
script are supported by the KOKKOS package. In this case data can stay
|
||||
on the GPU for many timesteps without being moved between the host and
|
||||
GPU, if you use the {device} value. If your script uses styles (e.g.
|
||||
fixes) which are not yet supported by the KOKKOS package, then data has
|
||||
to be move between the host and device anyway, so it is typically faster
|
||||
to let the host handle communication, by using the {host} value. Using
|
||||
{host} instead of {no} will enable use of multiple threads to
|
||||
pack/unpack communicated data. When running small systems on a GPU,
|
||||
performing the exchange pack/unpack on the host CPU can give speedup
|
||||
When running on CPUs or Xeon Phi, the {host} and {device} values work
|
||||
identically. When using GPUs, the {device} value is the default since it
|
||||
will typically be optimal if all of your styles used in your input
|
||||
script are supported by the KOKKOS package. In this case data can stay
|
||||
on the GPU for many timesteps without being moved between the host and
|
||||
GPU, if you use the {device} value. If your script uses styles (e.g.
|
||||
fixes) which are not yet supported by the KOKKOS package, then data has
|
||||
to be move between the host and device anyway, so it is typically faster
|
||||
to let the host handle communication, by using the {host} value. Using
|
||||
{host} instead of {no} will enable use of multiple threads to
|
||||
pack/unpack communicated data. When running small systems on a GPU,
|
||||
performing the exchange pack/unpack on the host CPU can give speedup
|
||||
since it reduces the number of CUDA kernel launches.
|
||||
|
||||
The {cuda/aware} keyword chooses whether CUDA-aware MPI will be used. When
|
||||
this keyword is set to {on}, buffers in GPU memory are passed directly
|
||||
through MPI send/receive calls. This reduces overhead of first copying
|
||||
the data to the host CPU. However CUDA-aware MPI is not supported on all
|
||||
systems, which can lead to segmentation faults and would require using a
|
||||
value of {off}. If LAMMPS can safely detect that CUDA-aware MPI is not
|
||||
available (currently only possible with OpenMPI v2.0.0 or later), then
|
||||
the {cuda/aware} keyword is automatically set to {off} by default. When
|
||||
the {cuda/aware} keyword is set to {off} while any of the {comm}
|
||||
keywords are set to {device}, the value for these {comm} keywords will
|
||||
be automatically changed to {host}. This setting has no effect if not
|
||||
running on GPUs. CUDA-aware MPI is available for OpenMPI 1.8 (or later
|
||||
The {cuda/aware} keyword chooses whether CUDA-aware MPI will be used. When
|
||||
this keyword is set to {on}, buffers in GPU memory are passed directly
|
||||
through MPI send/receive calls. This reduces overhead of first copying
|
||||
the data to the host CPU. However CUDA-aware MPI is not supported on all
|
||||
systems, which can lead to segmentation faults and would require using a
|
||||
value of {off}. If LAMMPS can safely detect that CUDA-aware MPI is not
|
||||
available (currently only possible with OpenMPI v2.0.0 or later), then
|
||||
the {cuda/aware} keyword is automatically set to {off} by default. When
|
||||
the {cuda/aware} keyword is set to {off} while any of the {comm}
|
||||
keywords are set to {device}, the value for these {comm} keywords will
|
||||
be automatically changed to {host}. This setting has no effect if not
|
||||
running on GPUs. CUDA-aware MPI is available for OpenMPI 1.8 (or later
|
||||
versions), Mvapich2 1.9 (or later) when the "MV2_USE_CUDA" environment
|
||||
variable is set to "1", CrayMPI, and IBM Spectrum MPI when the "-gpu"
|
||||
flag is used.
|
||||
@ -641,16 +641,16 @@ not used, you must invoke the package intel command in your input
|
||||
script or via the "-pk intel" "command-line
|
||||
switch"_Run_options.html.
|
||||
|
||||
For the KOKKOS package, the option defaults for GPUs are neigh = full,
|
||||
neigh/qeq = full, newton = off, binsize for GPUs = 2x LAMMPS default
|
||||
value, comm = device, cuda/aware = on. When LAMMPS can safely detect
|
||||
that CUDA-aware MPI is not available, the default value of cuda/aware
|
||||
becomes "off". For CPUs or Xeon Phis, the option defaults are neigh =
|
||||
half, neigh/qeq = half, newton = on, binsize = 0.0, and comm = no. The
|
||||
option neigh/thread = on when there are 16K atoms or less on an MPI
|
||||
rank, otherwise it is "off". These settings are made automatically by
|
||||
the required "-k on" "command-line switch"_Run_options.html. You can
|
||||
change them by using the package kokkos command in your input script or
|
||||
For the KOKKOS package, the option defaults for GPUs are neigh = full,
|
||||
neigh/qeq = full, newton = off, binsize for GPUs = 2x LAMMPS default
|
||||
value, comm = device, cuda/aware = on. When LAMMPS can safely detect
|
||||
that CUDA-aware MPI is not available, the default value of cuda/aware
|
||||
becomes "off". For CPUs or Xeon Phis, the option defaults are neigh =
|
||||
half, neigh/qeq = half, newton = on, binsize = 0.0, and comm = no. The
|
||||
option neigh/thread = on when there are 16K atoms or less on an MPI
|
||||
rank, otherwise it is "off". These settings are made automatically by
|
||||
the required "-k on" "command-line switch"_Run_options.html. You can
|
||||
change them by using the package kokkos command in your input script or
|
||||
via the "-pk kokkos command-line switch"_Run_options.html.
|
||||
|
||||
For the OMP package, the default is Nthreads = 0 and the option
|
||||
|
||||
@ -20,8 +20,8 @@ If the {preset} keyword is given, no others are needed.
|
||||
Otherwise, all are mandatory except for {neigh}.
|
||||
The {neigh} keyword is always optional. :l
|
||||
{preset} arg = {2011} or {2015} = which set of predefined parameters to use
|
||||
2011 = use the potential parameters from "(Tainter 2011)"_#Tainter2011
|
||||
2015 = use the potential parameters from "(Tainter 2015)"_#Tainter2015
|
||||
2011 = use the potential parameters from "(Tainter 2011)"_#Tainter2011
|
||||
2015 = use the potential parameters from "(Tainter 2015)"_#Tainter2015
|
||||
{Ea} arg = three-body energy for type A hydrogen bonding interactions (energy units)
|
||||
{Eb} arg = three-body energy for type B hydrogen bonding interactions (energy units)
|
||||
{Ec} arg = three-body energy for type C hydrogen bonding interactions (energy units)
|
||||
|
||||
@ -100,7 +100,7 @@ on particle {i} due to contact with particle {j} is given by:
|
||||
\mathbf\{F\}_\{ne, Hooke\} = k_N \delta_\{ij\} \mathbf\{n\}
|
||||
\end\{equation\}
|
||||
|
||||
Where \(\delta = R_i + R_j - \|\mathbf\{r\}_\{ij\}\|\) is the particle
|
||||
Where \(\delta_\{ij\} = R_i + R_j - \|\mathbf\{r\}_\{ij\}\|\) is the particle
|
||||
overlap, \(R_i, R_j\) are the particle radii, \(\mathbf\{r\}_\{ij\} =
|
||||
\mathbf\{r\}_i - \mathbf\{r\}_j\) is the vector separating the two
|
||||
particle centers (note the i-j ordering so that \(F_\{ne\}\) is
|
||||
@ -177,7 +177,7 @@ following general form:
|
||||
\end\{equation\}
|
||||
|
||||
Here, \(\mathbf\{v\}_\{n,rel\} = (\mathbf\{v\}_j - \mathbf\{v\}_i)
|
||||
\cdot \mathbf\{n\}\) is the component of relative velocity along
|
||||
\cdot \mathbf\{n\} \mathbf\{n\}\) is the component of relative velocity along
|
||||
\(\mathbf\{n\}\).
|
||||
|
||||
The optional {damping} keyword to the {pair_coeff} command followed by
|
||||
@ -299,8 +299,8 @@ the normal damping \(\eta_n\) (see above):
|
||||
\eta_t = -x_\{\gamma,t\} \eta_n
|
||||
\end\{equation\}
|
||||
|
||||
The normal damping prefactor \(\eta_n\) is determined by the choice of
|
||||
the {damping} keyword, as discussed above. Thus, the {damping}
|
||||
The normal damping prefactor \(\eta_n\) is determined by the choice
|
||||
of the {damping} keyword, as discussed above. Thus, the {damping}
|
||||
keyword also affects the tangential damping. The parameter
|
||||
\(x_\{\gamma,t\}\) is a scaling coefficient. Several works in the
|
||||
literature use \(x_\{\gamma,t\} = 1\) ("Marshall"_#Marshall2009,
|
||||
@ -308,10 +308,10 @@ literature use \(x_\{\gamma,t\} = 1\) ("Marshall"_#Marshall2009,
|
||||
tangential velocity at the point of contact is given by
|
||||
\(\mathbf\{v\}_\{t, rel\} = \mathbf\{v\}_\{t\} - (R_i\Omega_i +
|
||||
R_j\Omega_j) \times \mathbf\{n\}\), where \(\mathbf\{v\}_\{t\} =
|
||||
\mathbf\{v\}_r - \mathbf\{v\}_r\cdot\mathbf\{n\}\), \(\mathbf\{v\}_r =
|
||||
\mathbf\{v\}_j - \mathbf\{v\}_i\). The direction of the applied force
|
||||
is \(\mathbf\{t\} =
|
||||
\mathbf\{v_\{t,rel\}\}/\|\mathbf\{v_\{t,rel\}\}\|\).
|
||||
\mathbf\{v\}_r - \mathbf\{v\}_r\cdot\mathbf\{n\}\{n\}\),
|
||||
\(\mathbf\{v\}_r = \mathbf\{v\}_j - \mathbf\{v\}_i\).
|
||||
The direction of the applied force is \(\mathbf\{t\} =
|
||||
\mathbf\{v_\{t,rel\}\}/\|\mathbf\{v_\{t,rel\}\}\|\) .
|
||||
|
||||
The normal force value \(F_\{n0\}\) used to compute the critical force
|
||||
depends on the form of the contact model. For non-cohesive models
|
||||
@ -411,8 +411,8 @@ option by an additional factor of {a}, the radius of the contact region. The tan
|
||||
\mathbf\{F\}_t = -min(\mu_t F_\{n0\}, \|-k_t a \mathbf\{\xi\} + \mathbf\{F\}_\mathrm\{t,damp\}\|) \mathbf\{t\}
|
||||
\end\{equation\}
|
||||
|
||||
Here, {a} is the radius of the contact region, given by \(a = \delta
|
||||
R\) for all normal contact models, except for {jkr}, where it is given
|
||||
Here, {a} is the radius of the contact region, given by \(a =\sqrt\{R\delta\}\)
|
||||
for all normal contact models, except for {jkr}, where it is given
|
||||
implicitly by \(\delta = a^2/R - 2\sqrt\{\pi \gamma a/E\}\), see
|
||||
discussion above. To match the Mindlin solution, one should set \(k_t
|
||||
= 8G\), where \(G\) is the shear modulus, related to Young's modulus
|
||||
@ -680,7 +680,7 @@ The single() function of these pair styles returns 0.0 for the energy
|
||||
of a pairwise interaction, since energy is not conserved in these
|
||||
dissipative potentials. It also returns only the normal component of
|
||||
the pairwise interaction force. However, the single() function also
|
||||
calculates 10 extra pairwise quantities. The first 3 are the
|
||||
calculates 12 extra pairwise quantities. The first 3 are the
|
||||
components of the tangential force between particles I and J, acting
|
||||
on particle I. The 4th is the magnitude of this tangential force.
|
||||
The next 3 (5-7) are the components of the rolling torque acting on
|
||||
@ -790,4 +790,4 @@ alternative contact force models during inelastic collisions. Powder
|
||||
Technology, 233, 30-46.
|
||||
|
||||
:link(WaltonPC)
|
||||
[(Otis R. Walton)] Walton, O.R., Personal Communication
|
||||
[(Otis R. Walton)] Walton, O.R., Personal Communication
|
||||
|
||||
@ -43,8 +43,8 @@ when the tapper function is turned off. The formula of taper function
|
||||
can be found in pair style "ilp/graphene/hbn"_pair_ilp_graphene_hbn.html.
|
||||
|
||||
NOTE: This potential (ILP) is intended for interlayer interactions between two
|
||||
different layers of graphene. To perform a realistic simulation, this potential
|
||||
must be used in combination with intralayer potential, such as
|
||||
different layers of graphene. To perform a realistic simulation, this potential
|
||||
must be used in combination with intralayer potential, such as
|
||||
"AIREBO"_pair_airebo.html or "Tersoff"_pair_tersoff.html potential.
|
||||
To keep the intralayer properties unaffected, the interlayer interaction
|
||||
within the same layers should be avoided. Hence, each atom has to have a layer
|
||||
|
||||
207
doc/src/pair_local_density.txt
Normal file
@ -0,0 +1,207 @@
|
||||
"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
|
||||
|
||||
:link(lws,http://lammps.sandia.gov)
|
||||
:link(ld,Manual.html)
|
||||
:link(lc,Commands_all.html)
|
||||
|
||||
:line
|
||||
|
||||
pair_style local/density command :h3
|
||||
|
||||
[Syntax:]
|
||||
|
||||
pair_style style arg :pre
|
||||
|
||||
style = {local/density}
|
||||
arg = name of file containing tabulated values of local density and the potential :ul
|
||||
|
||||
[Examples:]
|
||||
|
||||
pair_style local/density benzene_water.localdensity.table :pre
|
||||
|
||||
pair_style hybrid/overlay table spline 500 local/density
|
||||
pair_coeff * * local/density benzene_water.localdensity.table :pre
|
||||
|
||||
[Description:]
|
||||
|
||||
The local density (LD) potential is a mean-field manybody potential, and, in some
|
||||
sense,a generalization of embedded atom models (EAM). The name "local density
|
||||
potential" arises from the fact that it assigns an energy to an atom depending
|
||||
on the number of neighboring atoms of given type around it within a predefined
|
||||
spherical volume (i.e., within a cutoff). The bottom-up coarse-graining (CG)
|
||||
literature suggests that such potentials can be widely useful in capturing
|
||||
effective multibody forces in a computationally efficient manner so as to
|
||||
improve the quality of CG models of implicit solvation"(Sanyal1)"_#Sanyal1 and
|
||||
phase-segregation in liquid mixtures"(Sanyal2)"_#Sanyal2, and provide guidelines
|
||||
to determine the extent of manybody correlations present in a CG
|
||||
model."(Rosenberger)"_#Rosenberger The LD potential in LAMMPS is primarily
|
||||
intended to be used as a corrective potential over traditional pair potentials
|
||||
in bottom-up CG models, i.e., as a hybrid pair style with
|
||||
other explicit pair interaction terms (e.g., table spline, Lennard Jones, etc.).
|
||||
Because the LD potential is not a pair potential per se, it is implemented
|
||||
simply as a single auxiliary file with all specifications that will be read
|
||||
upon initialization.
|
||||
|
||||
NOTE: Thus when used as the only interaction in the system, there is no
|
||||
corresponding pair_coeff command and when used with other pair styles using the
|
||||
hybrid/overlay option, the corresponding pair_coeff command must be supplied
|
||||
* * as placeholders for the atom types.
|
||||
|
||||
:line
|
||||
|
||||
[System with a single CG atom type:]
|
||||
|
||||
A system of a single atom type (e.g., LJ argon) with a single local density (LD)
|
||||
potential would have an energy given by:
|
||||
|
||||
:c,image(Eqs/pair_local_density_energy.jpg)
|
||||
|
||||
where rho_i is the LD at atom i and F(rho) is similar in spirit to the
|
||||
embedding function used in EAM potentials. The LD at atom i is given by the sum
|
||||
|
||||
:c,image(Eqs/pair_local_density_ld.jpg)
|
||||
|
||||
where phi is an indicator function that is one at r=0 and zero beyond a cutoff
|
||||
distance R2. The choice of the functional form of phi is somewhat arbitrary,
|
||||
but the following piecewise cubic function has proven sufficiently general:
|
||||
"(Sanyal1)"_#Sanyal1, "(Sanyal2)"_#Sanyal2 "(Rosenberger)"_#Rosenberger
|
||||
|
||||
:c,image(Eqs/pair_local_density_indicator_func.jpg)
|
||||
|
||||
The constants {c} are chosen so that the indicator function smoothly
|
||||
interpolates between 1 and 0 between the distances R1 and R2, which are
|
||||
called the inner and outer cutoffs, respectively. Thus phi satisfies
|
||||
phi(R1) = 1, phi(R2) = dphi/dr @ (r=R1) = dphi/dr @ (r=R2) = 0. The embedding
|
||||
function F(rho) may or may not have a closed-form expression. To maintain
|
||||
generality, it is practically represented with a spline-interpolated table
|
||||
over a predetermined range of rho. Outside of that range it simply adopts zero
|
||||
values at the endpoints.
|
||||
|
||||
It can be shown that the total force between two atoms due to the LD potential
|
||||
takes the form of a pair force, which motivates its designation as a LAMMPS
|
||||
pair style. Please see "(Sanyal1)"_#Sanyal1 for details of the derivation.
|
||||
|
||||
:line
|
||||
|
||||
[Systems with arbitrary numbers of atom types:]
|
||||
|
||||
The potential is easily generalized to systems involving multiple atom types:
|
||||
|
||||
:c,image(Eqs/pair_local_density_energy_multi.jpg)
|
||||
|
||||
with the LD expressed as
|
||||
|
||||
:c,image(Eqs/pair_local_density_ld_multi.jpg)
|
||||
|
||||
where alpha gives the type of atom i, beta the type of atom j, and the
|
||||
coefficients a and b filter for atom types as specified by the user. a is
|
||||
called the central atom filter as it determines to which atoms the
|
||||
potential applies; a_alpha = 1 if the LD potential applies to atom type alpha
|
||||
else zero. On the other hand, b is called the neighbor atom filter because it
|
||||
specifies which atom types to use in the calculation of the LD; b_beta = 1 if
|
||||
atom type beta contributes to the LD and zero otherwise.
|
||||
|
||||
NOTE: Note that the potentials need not be symmetric with respect to atom types,
|
||||
which is the reason for two distinct sets of coefficients a and b. An atom type
|
||||
may contribute to the LD but not the potential, or to the potential but not the
|
||||
LD. Such decisions are made by the user and should (ideally) be motivated on
|
||||
physical grounds for the problem at hand.
|
||||
|
||||
:line
|
||||
|
||||
[General form for implementation in LAMMPS:]
|
||||
|
||||
Of course, a system with many atom types may have many different possible LD
|
||||
potentials, each with their own atom type filters, cutoffs, and embedding
|
||||
functions. The most general form of this potential as implemented in the
|
||||
pair_style local/density is:
|
||||
|
||||
:c,image(Eqs/pair_local_density_energy_implement.jpg)
|
||||
|
||||
where, k is an index that spans the (arbitrary) number of applied LD potentials
|
||||
N_LD. Each LD is calculated as before with:
|
||||
|
||||
:c,image(Eqs/pair_local_density_ld_implement.jpg)
|
||||
|
||||
The superscript on the indicator function phi simply indicates that it is
|
||||
associated with specific values of the cutoff distances R1(k) and R2(k). In
|
||||
summary, there may be N_LD distinct LD potentials. With each potential type (k),
|
||||
one must specify:
|
||||
|
||||
the inner and outer cutoffs as R1 and R2
|
||||
the central type filter a(k), where k = 1,2,...N_LD
|
||||
the neighbor type filter b(k), where k = 1,2,...N_LD
|
||||
the LD potential function F(k)(rho), typically as a table that is later spline-interpolated :ul
|
||||
|
||||
:line
|
||||
|
||||
[Tabulated input file format:]
|
||||
|
||||
Line 1: comment or blank (ignored)
|
||||
Line 2: comment or blank (ignored)
|
||||
Line 3: N_LD N_rho (# of LD potentials and # of tabulated values, single space separated)
|
||||
Line 4: blank (ignored)
|
||||
Line 5: R1(k) R2(k) (lower and upper cutoffs, single space separated)
|
||||
Line 6: central-types (central atom types, single space separated)
|
||||
Line 7: neighbor-types (neighbor atom types single space separated)
|
||||
Line 8: rho_min rho_max drho (min, max and diff. in tabulated rho values, single space separated)
|
||||
Line 9: F(k)(rho_min + 0.drho)
|
||||
Line 10: F(k)(rho_min + 1.drho)
|
||||
Line 11: F(k)(rho_min + 2.drho)
|
||||
...
|
||||
Line 9+N_rho: F(k)(rho_min + N_rho . drho)
|
||||
Line 10+N_rho: blank (ignored) :pre
|
||||
|
||||
Block 2 :pre
|
||||
|
||||
Block 3 :pre
|
||||
|
||||
Block N_LD :pre
|
||||
|
||||
Lines 5 to 9+N_rho constitute the first block. Thus the input file is separated
|
||||
(by blank lines) into N_LD blocks each representing a separate LD potential and
|
||||
each specifying its own upper and lower cutoffs, central and neighbor atoms,
|
||||
and potential. In general, blank lines anywhere are ignored.
|
||||
|
||||
:line
|
||||
|
||||
[Mixing, shift, table, tail correction, restart, info]:
|
||||
This pair style does not support automatic mixing. For atom type pairs alpha,
|
||||
beta and alpha != beta, even if LD potentials of type (alpha, alpha) and
|
||||
(beta, beta) are provided, you will need to explicitly provide LD potential
|
||||
types (alpha, beta) and (beta, alpha) if need be (Here, the notation (alpha,
|
||||
beta) means that alpha is the central atom to which the LD potential is applied
|
||||
and beta is the neighbor atom which contributes to the LD potential on alpha).
|
||||
|
||||
This pair style does not support the "pair_modify"_pair_modify.html
|
||||
shift, table, and tail options.
|
||||
|
||||
The local/density pair style does not write its information to "binary restart
|
||||
files"_restart.html, since it is stored in tabulated potential files.
|
||||
Thus, you need to re-specify the pair_style and pair_coeff commands in
|
||||
an input script that reads a restart file.
|
||||
|
||||
:line
|
||||
|
||||
[Restrictions:]
|
||||
|
||||
The local/density pair style is a part of the USER-MISC package. It is only
|
||||
enabled if LAMMPS was built with that package. See the "Build
|
||||
package"_Build_package.html doc page for more info.
|
||||
|
||||
[Related commands:]
|
||||
|
||||
"pair_coeff"_pair_coeff.html
|
||||
|
||||
[Default:] none
|
||||
|
||||
:line
|
||||
|
||||
|
||||
:link(Sanyal1)
|
||||
[(Sanyal1)] Sanyal and Shell, Journal of Chemical Physics, 2016, 145 (3), 034109.
|
||||
:link(Sanyal2)
|
||||
[(Sanyal2)] Sanyal and Shell, Journal of Physical Chemistry B, 122 (21), 5678-5693.
|
||||
|
||||
:link(Rosenberger)
|
||||
[(Rosenberger)] Rosenberger, Sanyal, Shell and van der Vegt, Journal of Chemical Physics, 2019, 151 (4), 044111.
|
||||
@ -68,7 +68,7 @@ gamma (distance) :ul
|
||||
|
||||
[Mixing, shift, table, tail correction, restart, rRESPA info]:
|
||||
|
||||
Mixing rules are fixed for this style as defined above.
|
||||
Mixing rules are fixed for this style as defined above.
|
||||
|
||||
Shifting the potential energy is not necessary because the switching
|
||||
function ensures that the potential is zero at the cut-off.
|
||||
|
||||
@ -27,8 +27,8 @@ args = list of arguments for these particular styles :ul
|
||||
{oxdna2/stk} args = seq T xi kappa 6.0 0.4 0.9 0.32 0.6 1.3 0 0.8 0.9 0 0.95 0.9 0 0.95 2.0 0.65 2.0 0.65
|
||||
seq = seqav (for average sequence stacking strength) or seqdep (for sequence-dependent stacking strength)
|
||||
T = temperature (oxDNA units, 0.1 = 300 K)
|
||||
xi = temperature-independent coefficient in stacking strength
|
||||
kappa = coefficient of linear temperature dependence in stacking strength
|
||||
xi = temperature-independent coefficient in stacking strength
|
||||
kappa = coefficient of linear temperature dependence in stacking strength
|
||||
{oxdna2/hbond} args = seq eps 8.0 0.4 0.75 0.34 0.7 1.5 0 0.7 1.5 0 0.7 1.5 0 0.7 0.46 3.141592653589793 0.7 4.0 1.5707963267948966 0.45 4.0 1.5707963267948966 0.45
|
||||
seq = seqav (for average sequence base-pairing strength) or seqdep (for sequence-dependent base-pairing strength)
|
||||
eps = 1.0678 (between base pairs A-T and C-G) or 0 (all other pairs)
|
||||
|
||||
@ -50,7 +50,7 @@ the SNAP potential files themselves.
|
||||
Only a single pair_coeff command is used with the {snap} style which
|
||||
specifies a SNAP coefficient file followed by a SNAP parameter file
|
||||
and then N additional arguments specifying the mapping of SNAP
|
||||
elements to LAMMPS atom types, where N is the number of
|
||||
elements to LAMMPS atom types, where N is the number of
|
||||
LAMMPS atom types:
|
||||
|
||||
SNAP coefficient file
|
||||
@ -79,7 +79,7 @@ The name of the SNAP coefficient file usually ends in the
|
||||
".snapcoeff" extension. It may contain coefficients
|
||||
for many SNAP elements. The only requirement is that it
|
||||
contain at least those element names appearing in the
|
||||
LAMMPS mapping list.
|
||||
LAMMPS mapping list.
|
||||
The name of the SNAP parameter file usually ends in the ".snapparam"
|
||||
extension. It contains a small number
|
||||
of parameters that define the overall form of the SNAP potential.
|
||||
|
||||
@ -11,7 +11,7 @@ pair_style spin/dipole/long command :h3
|
||||
|
||||
[Syntax:]
|
||||
|
||||
pair_style spin/dipole/cut cutoff
|
||||
pair_style spin/dipole/cut cutoff
|
||||
pair_style spin/dipole/long cutoff :pre
|
||||
|
||||
cutoff = global cutoff for magnetic dipole energy and forces
|
||||
@ -21,35 +21,34 @@ cutoff = global cutoff for magnetic dipole energy and forces
|
||||
[Examples:]
|
||||
|
||||
pair_style spin/dipole/cut 10.0
|
||||
pair_coeff * * 10.0
|
||||
pair_coeff * * 10.0
|
||||
pair_coeff 2 3 8.0 :pre
|
||||
|
||||
pair_style spin/dipole/long 9.0
|
||||
pair_coeff * * 1.0 1.0
|
||||
pair_coeff 2 3 1.0 1.0 2.5 4.0 scale 0.5
|
||||
pair_coeff 2 3 1.0 1.0 2.5 4.0 :pre
|
||||
pair_coeff * * 10.0
|
||||
pair_coeff 2 3 6.0 :pre
|
||||
|
||||
[Description:]
|
||||
|
||||
Style {spin/dipole/cut} computes a short-range dipole-dipole
|
||||
interaction between pairs of magnetic particles that each
|
||||
have a magnetic spin.
|
||||
interaction between pairs of magnetic particles that each
|
||||
have a magnetic spin.
|
||||
The magnetic dipole-dipole interactions are computed by the
|
||||
following formulas for the magnetic energy, magnetic precession
|
||||
following formulas for the magnetic energy, magnetic precession
|
||||
vector omega and mechanical force between particles I and J.
|
||||
|
||||
:c,image(Eqs/pair_spin_dipole.jpg)
|
||||
|
||||
where si and sj are the spin on two magnetic particles,
|
||||
r is their separation distance, and the vector e = (Ri - Rj)/|Ri - Rj|
|
||||
is the direction vector between the two particles.
|
||||
where si and sj are the spin on two magnetic particles,
|
||||
r is their separation distance, and the vector e = (Ri - Rj)/|Ri - Rj|
|
||||
is the direction vector between the two particles.
|
||||
|
||||
Style {spin/dipole/long} computes long-range magnetic dipole-dipole
|
||||
interaction.
|
||||
A "kspace_style"_kspace_style.html must be defined to
|
||||
use this pair style. Currently, "kspace_style
|
||||
use this pair style. Currently, "kspace_style
|
||||
ewald/dipole/spin"_kspace_style.html and "kspace_style
|
||||
pppm/dipole/spin"_kspace_style.html support long-range magnetic
|
||||
pppm/dipole/spin"_kspace_style.html support long-range magnetic
|
||||
dipole-dipole interactions.
|
||||
|
||||
:line
|
||||
@ -68,8 +67,8 @@ to be specified in an input script that reads a restart file.
|
||||
[Restrictions:]
|
||||
|
||||
The {spin/dipole/cut} and {spin/dipole/long} styles are part of
|
||||
the SPIN package. They are only enabled if LAMMPS was built with that
|
||||
package. See the "Build package"_Build_package.html doc page for more
|
||||
the SPIN package. They are only enabled if LAMMPS was built with that
|
||||
package. See the "Build package"_Build_package.html doc page for more
|
||||
info.
|
||||
|
||||
Using dipole/spin pair styles with {electron} "units"_units.html is not
|
||||
|
||||
@ -15,11 +15,11 @@ pair_style spin/dmi cutoff :pre
|
||||
cutoff = global cutoff pair (distance in metal units) :ulb,l
|
||||
|
||||
:ule
|
||||
|
||||
|
||||
[Examples:]
|
||||
|
||||
pair_style spin/dmi 4.0
|
||||
pair_coeff * * dmi 2.6 0.001 1.0 0.0 0.0
|
||||
pair_coeff * * dmi 2.6 0.001 1.0 0.0 0.0
|
||||
pair_coeff 1 2 dmi 4.0 0.00109 0.0 0.0 1.0 :pre
|
||||
|
||||
[Description:]
|
||||
|
||||
@ -15,7 +15,7 @@ pair_style spin/neel cutoff :pre
|
||||
cutoff = global cutoff pair (distance in metal units) :ulb,l
|
||||
|
||||
:ule
|
||||
|
||||
|
||||
[Examples:]
|
||||
|
||||
pair_style spin/neel 4.0
|
||||
|
||||
@ -228,6 +228,7 @@ accelerated styles exist.
|
||||
"lj/smooth/linear"_pair_lj_smooth_linear.html - linear smoothed LJ potential
|
||||
"lj/switch3/coulgauss"_pair_lj_switch3_coulgauss - smoothed LJ vdW potential with Gaussian electrostatics
|
||||
"lj96/cut"_pair_lj96.html - Lennard-Jones 9/6 potential
|
||||
"local/density"_pair_local_density.html - generalized basic local density potential
|
||||
"lubricate"_pair_lubricate.html - hydrodynamic lubrication forces
|
||||
"lubricate/poly"_pair_lubricate.html - hydrodynamic lubrication forces with polydispersity
|
||||
"lubricateU"_pair_lubricateU.html - hydrodynamic lubrication forces for Fast Lubrication Dynamics
|
||||
|
||||
@ -66,6 +66,7 @@ Pair Styles :h1
|
||||
pair_lj_smooth
|
||||
pair_lj_smooth_linear
|
||||
pair_lj_switch3_coulgauss
|
||||
pair_local_density
|
||||
pair_lubricate
|
||||
pair_lubricateU
|
||||
pair_mdf
|
||||
|
||||
62
doc/src/third_order.txt
Normal file
@ -0,0 +1,62 @@
|
||||
"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
|
||||
|
||||
:link(lws,http://lammps.sandia.gov)
|
||||
:link(ld,Manual.html)
|
||||
:link(lc,Commands_all.html)
|
||||
|
||||
:line
|
||||
|
||||
third_order command :h3
|
||||
|
||||
[Syntax:]
|
||||
|
||||
third_order group-ID style delta args keyword value ... :pre
|
||||
|
||||
group-ID = ID of group of atoms to displace :ulb,l
|
||||
style = {regular} or {eskm} :l
|
||||
delta = finite different displacement length (distance units) :l
|
||||
one or more keyword/arg pairs may be appended :l
|
||||
keyword = {file} or {binary}
|
||||
{file} name = name of output file for the third order tensor
|
||||
{binary} arg = {yes} or {no} or {gzip} :pre
|
||||
:ule
|
||||
|
||||
[Examples:]
|
||||
|
||||
third_order 1 regular 0.000001
|
||||
third_order 1 eskm 0.000001
|
||||
third_order 3 regular 0.00004 file third_order.dat
|
||||
third_order 5 eskm 0.00000001 file third_order.dat binary yes :pre
|
||||
|
||||
[Description:]
|
||||
|
||||
Calculate the third order force constant tensor by finite difference of the selected group,
|
||||
|
||||
:c,image(JPG/third_order_force_constant.png))
|
||||
|
||||
where Phi is the third order force constant tensor.
|
||||
|
||||
The output of the command is the tensor, three elements at a time. The
|
||||
three elements correspond to the three gamma elements for a specific i/alpha/j/beta/k.
|
||||
The initial five numbers are i, alpha, j, beta, and k respectively.
|
||||
|
||||
If the style eskm is selected, the tensor will be using energy units of 10 J/mol.
|
||||
These units conform to eskm style from the dynamical_matrix command, which
|
||||
will simplify operations using dynamical matrices with third order tensors.
|
||||
|
||||
[Restrictions:]
|
||||
|
||||
The command collects a 9 times the number of atoms in the group on every single MPI rank,
|
||||
so the memory requirements can be very significant for large systems.
|
||||
|
||||
This command is part of the USER-PHONON package. It is only enabled if
|
||||
LAMMPS was built with that package. See the "Build
|
||||
package"_Build_package.html doc page for more info.
|
||||
|
||||
[Related commands:]
|
||||
|
||||
"fix phonon"_fix_phonon.html "dynamical_matrix"_dynamical_matrix.html
|
||||
|
||||
[Default:]
|
||||
|
||||
The default settings are file = "third_order.dat", binary = no
|
||||
@ -276,6 +276,7 @@ Broadwell
|
||||
Broglie
|
||||
brownian
|
||||
brownw
|
||||
Broyden
|
||||
Bryantsev
|
||||
Btarget
|
||||
btype
|
||||
@ -306,6 +307,7 @@ Cavium
|
||||
Cawkwell
|
||||
cbecker
|
||||
ccache
|
||||
ccachepiecewise
|
||||
ccmake
|
||||
ccNspecies
|
||||
CCu
|
||||
@ -624,6 +626,7 @@ Doye
|
||||
dpd
|
||||
DPD
|
||||
dpdTheta
|
||||
dphi
|
||||
DPhil
|
||||
dr
|
||||
dR
|
||||
@ -782,6 +785,7 @@ erotate
|
||||
Ertas
|
||||
ervel
|
||||
Espanol
|
||||
eskm
|
||||
esu
|
||||
esub
|
||||
esw
|
||||
@ -991,6 +995,7 @@ gmask
|
||||
Gmask
|
||||
gneb
|
||||
GNEB
|
||||
Goldfarb
|
||||
googlemail
|
||||
Gordan
|
||||
GPa
|
||||
@ -1410,6 +1415,7 @@ Laupretre
|
||||
lavenderblush
|
||||
lawngreen
|
||||
lB
|
||||
lbfgs
|
||||
lbl
|
||||
LBtype
|
||||
lcbop
|
||||
@ -1583,6 +1589,7 @@ Materias
|
||||
mathbf
|
||||
matlab
|
||||
matplotlib
|
||||
Mattice
|
||||
Mattox
|
||||
Mattson
|
||||
maxangle
|
||||
@ -2046,6 +2053,7 @@ Orsi
|
||||
ortho
|
||||
orthonormal
|
||||
orthorhombic
|
||||
oso
|
||||
ot
|
||||
Otype
|
||||
Ouldridge
|
||||
@ -2130,6 +2138,7 @@ ph
|
||||
Phillpot
|
||||
phiphi
|
||||
phonon
|
||||
phonons
|
||||
phophorous
|
||||
phosphide
|
||||
Phs
|
||||
@ -2143,6 +2152,7 @@ picograms
|
||||
picosecond
|
||||
picoseconds
|
||||
pid
|
||||
piecewise
|
||||
Pieniazek
|
||||
Pieter
|
||||
pimd
|
||||
@ -2277,6 +2287,7 @@ qoffload
|
||||
qopenmp
|
||||
qoverride
|
||||
qtb
|
||||
quadratically
|
||||
quadrupolar
|
||||
Quant
|
||||
quartic
|
||||
@ -2427,6 +2438,7 @@ Rodrigues
|
||||
Rohart
|
||||
Ronchetti
|
||||
Rosati
|
||||
Rosenberger
|
||||
Rossky
|
||||
rosybrown
|
||||
rotationally
|
||||
@ -2491,6 +2503,7 @@ Scripta
|
||||
sdk
|
||||
sdpd
|
||||
SDPD
|
||||
se
|
||||
seagreen
|
||||
Secor
|
||||
sectoring
|
||||
@ -2517,6 +2530,7 @@ setvel
|
||||
sfftw
|
||||
Sg
|
||||
Shan
|
||||
Shanno
|
||||
shapex
|
||||
shapey
|
||||
shapez
|
||||
@ -2584,6 +2598,7 @@ Snodin
|
||||
Sodani
|
||||
Soderlind
|
||||
solvated
|
||||
solvation
|
||||
Sorensen
|
||||
soundspeed
|
||||
Souza
|
||||
@ -2946,6 +2961,7 @@ vectorial
|
||||
vectorization
|
||||
Vectorization
|
||||
vectorized
|
||||
Vegt
|
||||
vel
|
||||
Verlag
|
||||
verlet
|
||||
|
||||
@ -76,6 +76,7 @@ ellipse: ellipsoidal particles in spherical solvent, 2d system
|
||||
flow: Couette and Poiseuille flow in a 2d channel
|
||||
friction: frictional contact of spherical asperities between 2d surfaces
|
||||
gcmc: Grand Canonical Monte Carlo (GCMC) via the fix gcmc command
|
||||
gjf: use of fix langevin Gronbech-Jensen/Farago option
|
||||
granregion: use of fix wall/region/gran as boundary on granular particles
|
||||
hugoniostat: Hugoniostat shock dynamics
|
||||
hyper: global and local hyperdynamics of diffusion on Pt surface
|
||||
@ -99,12 +100,11 @@ pour: pouring of granular particles into a 3d box, then chute flow
|
||||
prd: parallel replica dynamics of vacancy diffusion in bulk Si
|
||||
python: use of PYTHON package to invoke Python code from input script
|
||||
qeq: use of QEQ package for charge equilibration
|
||||
reax: RDX and TATB models using the ReaxFF
|
||||
reax: RDX and TATB and several other models using ReaxFF
|
||||
rigid: rigid bodies modeled as independent or coupled
|
||||
shear: sideways shear applied to 2d solid, with and without a void
|
||||
snap: use of SNAP potential for Ta
|
||||
snap: examples for using several bundled SNAP potentials
|
||||
srd: stochastic rotation dynamics (SRD) particles as solvent
|
||||
snap: NVE dynamics for BCC tantalum crystal using SNAP potential
|
||||
steinhardt: Steinhardt-Nelson Q_l and W_l parameters usng orientorder/atom
|
||||
streitz: Streitz-Mintmire potential for Al2O3
|
||||
tad: temperature-accelerated dynamics of vacancy diffusion in bulk Si
|
||||
@ -164,6 +164,12 @@ The MC directory has an example script for using LAMMPS as an
|
||||
energy-evaluation engine in a iterative Monte Carlo energy-relaxation
|
||||
loop.
|
||||
|
||||
The UNITS directory contains examples of input scripts modeling the
|
||||
same Lennard-Jones liquid model, written in 3 different unit systems:
|
||||
lj, real, and metal. So that you can see how to scale/unscale input
|
||||
and output values read/written by LAMMPS to verify you are performing
|
||||
the same simulation in different unit systems.
|
||||
|
||||
The USER directory contains subdirectories of user-provided example
|
||||
scripts for ser packages. See the README files in those directories
|
||||
for more info. See the doc/Section_start.html file for more info
|
||||
|
||||
@ -32,7 +32,7 @@ neigh_modify every 10 check yes delay 20
|
||||
|
||||
fix 1 all precession/spin anisotropy 0.0000033 0.0 0.0 1.0
|
||||
fix 2 all langevin/spin 0.0 0.1 21
|
||||
fix 3 all nve/spin lattice no
|
||||
fix 3 all nve/spin lattice frozen
|
||||
|
||||
timestep 0.0002
|
||||
|
||||
|
||||
@ -35,7 +35,7 @@ fix_modify 1 energy yes
|
||||
|
||||
fix 2 all langevin/spin 0.0 0.0 21
|
||||
|
||||
fix 3 all nve/spin lattice yes
|
||||
fix 3 all nve/spin lattice moving
|
||||
timestep 0.0001
|
||||
|
||||
# compute and output options
|
||||
|
||||
@ -37,7 +37,7 @@ neigh_modify every 10 check yes delay 20
|
||||
fix 1 all precession/spin anisotropy 0.01 0.0 0.0 1.0
|
||||
#fix 2 all langevin/spin 0.0 0.0 21
|
||||
fix 2 all langevin/spin 0.0 0.1 21
|
||||
fix 3 all nve/spin lattice yes
|
||||
fix 3 all nve/spin lattice moving
|
||||
|
||||
timestep 0.0001
|
||||
|
||||
|
||||
@ -33,7 +33,7 @@ fix 1 all precession/spin cubic 0.001 0.0005 1.0 0.0 0.0 0.0 1.0 0.0 0.0 0.0 1
|
||||
fix_modify 1 energy yes
|
||||
fix 2 all langevin/spin 0.0 0.0 21
|
||||
|
||||
fix 3 all nve/spin lattice yes
|
||||
fix 3 all nve/spin lattice moving
|
||||
timestep 0.0001
|
||||
|
||||
# compute and output options
|
||||
|
||||
@ -35,7 +35,7 @@ fix 1 all precession/spin cubic 0.001 0.0005 1.0 0.0 0.0 0.0 1.0 0.0 0.0 0.0 1
|
||||
fix_modify 1 energy yes
|
||||
fix 2 all langevin/spin 0.0 0.0 21
|
||||
|
||||
fix 3 all nve/spin lattice yes
|
||||
fix 3 all nve/spin lattice moving
|
||||
timestep 0.0001
|
||||
|
||||
# compute and output options
|
||||
|
||||
@ -36,7 +36,7 @@ fix 1 all precession/spin cubic 0.001 0.0005 1.0 0.0 0.0 0.0 1.0 0.0 0.0 0.0 1
|
||||
fix_modify 1 energy yes
|
||||
fix 2 all langevin/spin 0.0 0.0 21
|
||||
|
||||
fix 3 all nve/spin lattice yes
|
||||
fix 3 all nve/spin lattice moving
|
||||
timestep 0.0001
|
||||
|
||||
# compute and output options
|
||||
|
||||
@ -33,7 +33,7 @@ neigh_modify every 10 check yes delay 20
|
||||
fix 1 all precession/spin zeeman 0.0 0.0 0.0 1.0
|
||||
fix 2 all langevin/spin 0.0 0.0 21
|
||||
|
||||
fix 3 all nve/spin lattice yes
|
||||
fix 3 all nve/spin lattice moving
|
||||
timestep 0.0001
|
||||
|
||||
# compute and output options
|
||||
|
||||
@ -31,7 +31,7 @@ fix 1 all precession/spin cubic 0.001 0.0005 1.0 0.0 0.0 0.0 1.0 0.0 0.0 0.0 1
|
||||
fix_modify 1 energy yes
|
||||
fix 2 all langevin/spin 0.0 0.0 21
|
||||
|
||||
fix 3 all nve/spin lattice yes
|
||||
fix 3 all nve/spin lattice moving
|
||||
timestep 0.0001
|
||||
|
||||
# compute and output options
|
||||
|
||||
@ -33,7 +33,7 @@ neigh_modify every 10 check yes delay 20
|
||||
fix 1 all precession/spin zeeman 0.0 0.0 0.0 1.0
|
||||
fix 2 all langevin/spin 0.0 0.0 21
|
||||
|
||||
fix 3 all nve/spin lattice yes
|
||||
fix 3 all nve/spin lattice moving
|
||||
timestep 0.0001
|
||||
|
||||
# compute and output options
|
||||
|
||||
@ -35,7 +35,7 @@ fix 1 all precession/spin cubic -0.0001 0.0 1.0 0.0 0.0 0.0 1.0 0.0 0.0 0.0 1.
|
||||
fix_modify 1 energy yes
|
||||
fix 2 all langevin/spin 0.0 0.0 21
|
||||
|
||||
fix 3 all nve/spin lattice yes
|
||||
fix 3 all nve/spin lattice moving
|
||||
timestep 0.0001
|
||||
|
||||
# compute and output options
|
||||
|
||||