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Merge branch 'post-patch-tweaks' into doc-styles-check

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This commit is contained in:
Axel Kohlmeyer
2020-01-11 19:04:38 -05:00
parent a38cf075db 84a975439a
commit 8f9c3a3a9c
11 changed files with 63 additions and 899 deletions
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2
doc/src/Build_extras.rst
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@ -203,7 +203,7 @@ inside the CMake build directory. If the KIM library is already on
your system (in a location CMake cannot find it), set the PKG\_CONFIG\_PATH
environment variable so that libkim-api can be found.
For using KIM web queries.
For using OpenKIM web queries in LAMMPS.
If LMP\_DEBUG\_CURL is set, the libcurl verbose mode will be on, and any
libcurl calls within the KIM web query display a lot of information about

96
doc/src/Commands_all.rst
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@ -25,26 +25,26 @@ An alphabetic list of all general LAMMPS commands.
* :doc:`atom_style <atom_style>`
* :doc:`balance <balance>`
* :doc:`bond_coeff <bond_coeff>`
* :doc:`bond\_style <bond_style>`
* :doc:`bond\_write <bond_write>`
* :doc:`bond_style <bond_style>`
* :doc:`bond_write <bond_write>`
* :doc:`boundary <boundary>`
* :doc:`box <box>`
* :doc:`change\_box <change_box>`
* :doc:`change_box <change_box>`
* :doc:`clear <clear>`
* :doc:`comm\_modify <comm_modify>`
* :doc:`comm\_style <comm_style>`
* :doc:`comm_modify <comm_modify>`
* :doc:`comm_style <comm_style>`
* :doc:`compute <compute>`
* :doc:`compute\_modify <compute_modify>`
* :doc:`create\_atoms <create_atoms>`
* :doc:`create\_bonds <create_bonds>`
* :doc:`create\_box <create_box>`
* :doc:`delete\_atoms <delete_atoms>`
* :doc:`delete\_bonds <delete_bonds>`
* :doc:`compute_modify <compute_modify>`
* :doc:`create_atoms <create_atoms>`
* :doc:`create_bonds <create_bonds>`
* :doc:`create_box <create_box>`
* :doc:`delete_atoms <delete_atoms>`
* :doc:`delete_bonds <delete_bonds>`
* :doc:`dielectric <dielectric>`
* :doc:`dihedral\_coeff <dihedral_coeff>`
* :doc:`dihedral\_style <dihedral_style>`
* :doc:`dihedral_coeff <dihedral_coeff>`
* :doc:`dihedral_style <dihedral_style>`
* :doc:`dimension <dimension>`
* :doc:`displace\_atoms <displace_atoms>`
* :doc:`displace_atoms <displace_atoms>`
* :doc:`dump <dump>`
* :doc:`dump adios <dump_adios>`
* :doc:`dump image <dump_image>`
@ -52,75 +52,77 @@ An alphabetic list of all general LAMMPS commands.
* :doc:`dump netcdf <dump_netcdf>`
* :doc:`dump netcdf/mpiio <dump_netcdf>`
* :doc:`dump vtk <dump_vtk>`
* :doc:`dump\_modify <dump_modify>`
* :doc:`dynamical\_matrix <dynamical_matrix>`
* :doc:`dump_modify <dump_modify>`
* :doc:`dynamical_matrix <dynamical_matrix>`
* :doc:`echo <echo>`
* :doc:`fix <fix>`
* :doc:`fix\_modify <fix_modify>`
* :doc:`fix_modify <fix_modify>`
* :doc:`group <group>`
* :doc:`group2ndx <group2ndx>`
* :doc:`hyper <hyper>`
* :doc:`if <if>`
* :doc:`improper\_coeff <improper_coeff>`
* :doc:`improper\_style <improper_style>`
* :doc:`improper_coeff <improper_coeff>`
* :doc:`improper_style <improper_style>`
* :doc:`include <include>`
* :doc:`info <info>`
* :doc:`jump <jump>`
* :doc:`kim\_init <kim_commands>`
* :doc:`kim\_interactions <kim_commands>`
* :doc:`kim\_query <kim_commands>`
* :doc:`kspace\_modify <kspace_modify>`
* :doc:`kspace\_style <kspace_style>`
* :doc:`kim_init <kim_commands>`
* :doc:`kim_interactions <kim_commands>`
* :doc:`kim_param <kim_commands>`
* :doc:`kim_query <kim_commands>`
* :doc:`kspace_modify <kspace_modify>`
* :doc:`kspace_style <kspace_style>`
* :doc:`label <label>`
* :doc:`lattice <lattice>`
* :doc:`log <log>`
* :doc:`mass <mass>`
* :doc:`message <message>`
* :doc:`minimize <minimize>`
* :doc:`min\_modify <min_modify>`
* :doc:`min\_style <min_style>`
* :doc:`min\_style spin <min_spin>`
* :doc:`min_modify <min_modify>`
* :doc:`min_style <min_style>`
* :doc:`min_style spin <min_spin>`
* :doc:`molecule <molecule>`
* :doc:`ndx2group <group2ndx>`
* :doc:`neb <neb>`
* :doc:`neb/spin <neb_spin>`
* :doc:`neigh\_modify <neigh_modify>`
* :doc:`neigh_modify <neigh_modify>`
* :doc:`neighbor <neighbor>`
* :doc:`newton <newton>`
* :doc:`next <next>`
* :doc:`package <package>`
* :doc:`pair\_coeff <pair_coeff>`
* :doc:`pair\_modify <pair_modify>`
* :doc:`pair\_write <pair_write>`
* :doc:`pair_coeff <pair_coeff>`
* :doc:`pair_modify <pair_modify>`
* :doc:`pair_write <pair_write>`
* :doc:`partition <partition>`
* :doc:`prd <prd>`
* :doc:`print <print>`
* :doc:`processors <processors>`
* :doc:`python <python>`
* :doc:`quit <quit>`
* :doc:`read\_data <read_data>`
* :doc:`read\_dump <read_dump>`
* :doc:`read\_restart <read_restart>`
* :doc:`read_data <read_data>`
* :doc:`read_dump <read_dump>`
* :doc:`read_restart <read_restart>`
* :doc:`region <region>`
* :doc:`replicate <replicate>`
* :doc:`rerun <rerun>`
* :doc:`reset\_ids <reset_ids>`
* :doc:`reset\_timestep <reset_timestep>`
* :doc:`reset_ids <reset_ids>`
* :doc:`reset_timestep <reset_timestep>`
* :doc:`restart <restart>`
* :doc:`run <run>`
* :doc:`run\_style <run_style>`
* :doc:`run_style <run_style>`
* :doc:`server <server>`
* :doc:`set <set>`
* :doc:`shell <shell>`
* :doc:`special\_bonds <special_bonds>`
* :doc:`special_bonds <special_bonds>`
* :doc:`suffix <suffix>`
* :doc:`tad <tad>`
* :doc:`temper <temper>`
* :doc:`temper/grem <temper_grem>`
* :doc:`temper/npt <temper_npt>`
* :doc:`thermo <thermo>`
* :doc:`thermo\_modify <thermo_modify>`
* :doc:`thermo\_style <thermo_style>`
* :doc:`third\_order <third_order>`
* :doc:`thermo_modify <thermo_modify>`
* :doc:`thermo_style <thermo_style>`
* :doc:`third_order <third_order>`
* :doc:`timer <timer>`
* :doc:`timestep <timestep>`
* :doc:`uncompute <uncompute>`
@ -129,7 +131,11 @@ An alphabetic list of all general LAMMPS commands.
* :doc:`units <units>`
* :doc:`variable <variable>`
* :doc:`velocity <velocity>`
* :doc:`write\_coeff <write_coeff>`
* :doc:`write\_data <write_data>`
* :doc:`write\_dump <write_dump>`
* :doc:`write\_restart <write_restart>`
* :doc:`write_coeff <write_coeff>`
* :doc:`write_data <write_data>`
* :doc:`write_dump <write_dump>`
* :doc:`write_restart <write_restart>`
*
*
*
*

6
doc/src/Commands_bond.rst
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@ -44,12 +44,10 @@ OPT.
* :doc:`nonlinear (o) <bond_nonlinear>`
* :doc:`oxdna/fene <bond_oxdna>`
* :doc:`oxdna2/fene <bond_oxdna>`
* :doc:`oxrna2/fene <bond_oxdna>`
* :doc:`quartic (o) <bond_quartic>`
* :doc:`table (o) <bond_table>`
*
*
---
.. _angle:
@ -93,8 +91,6 @@ OPT.
* :doc:`table (o) <angle_table>`
*
---
.. _dihedral:
dihedral_style potentials

8
doc/src/Commands_pair.rst
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@ -11,10 +11,10 @@
* :ref:`Improper styles <improper>`
* :doc:`KSpace styles <Commands_kspace>`
Pair\_style potentials
Pair_style potentials
======================
All LAMMPS :doc:`pair\_style <pair_style>` commands. Some styles have
All LAMMPS :doc:`pair_style <pair_style>` commands. Some styles have
accelerated versions. This is indicated by additional letters in
parenthesis: g = GPU, i = USER-INTEL, k = KOKKOS, o = USER-OMP, t =
OPT.
@ -146,7 +146,7 @@ OPT.
* :doc:`lj/cut/soft (o) <pair_fep_soft>`
* :doc:`lj/cut/thole/long (o) <pair_thole>`
* :doc:`lj/cut/tip4p/cut (o) <pair_lj>`
* :doc:`lj/cut/tip4p/long (ot) <pair_lj>`
* :doc:`lj/cut/tip4p/long (got) <pair_lj>`
* :doc:`lj/cut/tip4p/long/soft (o) <pair_fep_soft>`
* :doc:`lj/expand (gko) <pair_lj_expand>`
* :doc:`lj/expand/coul/long (g) <pair_lj_expand>`
@ -209,7 +209,7 @@ OPT.
* :doc:`sdpd/taitwater/isothermal <pair_sdpd_taitwater_isothermal>`
* :doc:`smd/hertz <pair_smd_hertz>`
* :doc:`smd/tlsph <pair_smd_tlsph>`
* :doc:`smd/tri\_surface <pair_smd_triangulated_surface>`
* :doc:`smd/tri_surface <pair_smd_triangulated_surface>`
* :doc:`smd/ulsph <pair_smd_ulsph>`
* :doc:`smtbq <pair_smtbq>`
* :doc:`snap (k) <pair_snap>`

6
doc/src/pair_lj.rst
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@ -90,6 +90,9 @@ pair\_style lj/cut/coul/wolf/omp command
pair\_style lj/cut/tip4p/cut command
====================================
pair\_style lj/cut/tip4p/cut/gpu command
========================================
pair\_style lj/cut/tip4p/cut/omp command
========================================
@ -102,9 +105,6 @@ pair\_style lj/cut/tip4p/long/omp command
pair\_style lj/cut/tip4p/long/opt command
=========================================
pair\_style lj/cut/tip4p/long/gpu command
=====================================
Syntax
""""""

63
doc/txt/fix_nve_dot.txt
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@ -1,63 +0,0 @@
"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
fix nve/dot command :h3
[Syntax:]
fix ID group-ID nve/dot :pre
ID, group-ID are documented in "fix"_fix.html command :ulb,l
nve/dot = style name of this fix command :l
:ule
[Examples:]
fix 1 all nve/dot :pre
[Description:]
Apply a rigid-body integrator as described in "(Davidchack)"_#Davidchack1
to a group of atoms, but without Langevin dynamics.
This command performs Molecular dynamics (MD)
via a velocity-Verlet algorithm and an evolution operator that rotates
the quaternion degrees of freedom, similar to the scheme outlined in "(Miller)"_#Miller1.
This command is the equivalent of the "fix nve/dotc/langevin"_fix_nve_dotc_langevin.html
without damping and noise and can be used to determine the stability range
in a NVE ensemble prior to using the Langevin-type DOTC-integrator
(see also "fix nve/dotc/langevin"_fix_nve_dotc_langevin.html).
The command is equivalent to the "fix nve"_fix_nve.html.
The particles are always considered to have a finite size.
An example input file can be found in /examples/USER/cgdna/examples/duplex1/.
Further details of the implementation and stability of the integrator are contained in "(Henrich)"_#Henrich3.
The preprint version of the article can be found "here"_PDF/USER-CGDNA.pdf.
:line
[Restrictions:]
These pair styles can only be used if LAMMPS was built with the
"USER-CGDNA"_Package_details.html#PKG-USER-CGDNA package and the MOLECULE and ASPHERE package.
See the "Build package"_Build_package.html doc page for more info.
[Related commands:]
"fix nve/dotc/langevin"_fix_nve_dotc_langevin.html, "fix nve"_fix_nve.html
[Default:] none
:line
:link(Davidchack1)
[(Davidchack)] R.L Davidchack, T.E. Ouldridge, and M.V. Tretyakov. J. Chem. Phys. 142, 144114 (2015).
:link(Miller1)
[(Miller)] T. F. Miller III, M. Eleftheriou, P. Pattnaik, A. Ndirango, G. J. Martyna, J. Chem. Phys., 116, 8649-8659 (2002).
:link(Henrich3)
[(Henrich)] O. Henrich, Y. A. Gutierrez-Fosado, T. Curk, T. E. Ouldridge, Eur. Phys. J. E 41, 57 (2018).

143
doc/txt/fix_nve_dotc_langevin.txt
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@ -1,143 +0,0 @@
"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
fix nve/dotc/langevin command :h3
[Syntax:]
fix ID group-ID nve/dotc/langevin Tstart Tstop damp seed keyword value :pre
ID, group-ID are documented in "fix"_fix.html command :ulb,l
nve/dotc/langevin = style name of this fix command :l
Tstart,Tstop = desired temperature at start/end of run (temperature units) :l
damp = damping parameter (time units) :l
seed = random number seed to use for white noise (positive integer) :l
keyword = {angmom} :l
{angmom} value = factor
factor = do thermostat rotational degrees of freedom via the angular momentum and apply numeric scale factor as discussed below :pre
:ule
[Examples:]
fix 1 all nve/dotc/langevin 1.0 1.0 0.03 457145 angmom 10
fix 1 all nve/dotc/langevin 0.1 0.1 78.9375 457145 angmom 10 :pre
[Description:]
Apply a rigid-body Langevin-type integrator of the kind "Langevin C"
as described in "(Davidchack)"_#Davidchack2
to a group of atoms, which models an interaction with an implicit background
solvent. This command performs Brownian dynamics (BD)
via a technique that splits the integration into a deterministic Hamiltonian
part and the Ornstein-Uhlenbeck process for noise and damping.
The quaternion degrees of freedom are updated though an evolution
operator which performs a rotation in quaternion space, preserves
the quaternion norm and is akin to "(Miller)"_#Miller2.
In terms of syntax this command has been closely modelled on the
"fix langevin"_fix_langevin.html and its {angmom} option. But it combines
the "fix nve"_fix_nve.html and the "fix langevin"_fix_langevin.html in
one single command. The main feature is improved stability
over the standard integrator, permitting slightly larger timestep sizes.
NOTE: Unlike the "fix langevin"_fix_langevin.html this command performs
also time integration of the translational and quaternion degrees of freedom.
The total force on each atom will have the form:
F = Fc + Ff + Fr
Ff = - (m / damp) v
Fr is proportional to sqrt(Kb T m / (dt damp)) :pre
Fc is the conservative force computed via the usual inter-particle
interactions ("pair_style"_pair_style.html,
"bond_style"_bond_style.html, etc).
The Ff and Fr terms are implicitly taken into account by this fix
on a per-particle basis.
Ff is a frictional drag or viscous damping term proportional to the
particle's velocity. The proportionality constant for each atom is
computed as m/damp, where m is the mass of the particle and damp is
the damping factor specified by the user.
Fr is a force due to solvent atoms at a temperature T randomly bumping
into the particle. As derived from the fluctuation/dissipation
theorem, its magnitude as shown above is proportional to sqrt(Kb T m /
dt damp), where Kb is the Boltzmann constant, T is the desired
temperature, m is the mass of the particle, dt is the timestep size,
and damp is the damping factor. Random numbers are used to randomize
the direction and magnitude of this force as described in
"(Dunweg)"_#Dunweg3, where a uniform random number is used (instead of
a Gaussian random number) for speed.
:line
{Tstart} and {Tstop} have to be constant values, i.e. they cannot
be variables. If used together with the oxDNA force field for
coarse-grained simulation of DNA please note that T = 0.1 in oxDNA units
corresponds to T = 300 K.
The {damp} parameter is specified in time units and determines how
rapidly the temperature is relaxed. For example, a value of 0.03
means to relax the temperature in a timespan of (roughly) 0.03 time
units tau (see the "units"_units.html command).
The damp factor can be thought of as inversely related to the
viscosity of the solvent, i.e. a small relaxation time implies a
hi-viscosity solvent and vice versa. See the discussion about gamma
and viscosity in the documentation for the "fix
viscous"_fix_viscous.html command for more details.
Note that the value 78.9375 in the second example above corresponds
to a diffusion constant, which is about an order of magnitude larger
than realistic ones. This has been used to sample configurations faster
in Brownian dynamics simulations.
The random # {seed} must be a positive integer. A Marsaglia random
number generator is used. Each processor uses the input seed to
generate its own unique seed and its own stream of random numbers.
Thus the dynamics of the system will not be identical on two runs on
different numbers of processors.
The keyword/value option has to be used in the following way:
This fix has to be used together with the {angmom} keyword. The
particles are always considered to have a finite size.
The keyword {angmom} enables thermostatting of the rotational degrees of
freedom in addition to the usual translational degrees of freedom.
The scale factor after the {angmom} keyword gives the ratio of the rotational to
the translational friction coefficient.
An example input file can be found in /examples/USER/cgdna/examples/duplex2/.
Further details of the implementation and stability of the integrators are contained in "(Henrich)"_#Henrich4.
The preprint version of the article can be found "here"_PDF/USER-CGDNA.pdf.
:line
[Restrictions:]
These pair styles can only be used if LAMMPS was built with the
"USER-CGDNA"_Package_details.html#PKG-USER-CGDNA package and the MOLECULE and ASPHERE package.
See the "Build package"_Build_package.html doc page for more info.
[Related commands:]
"fix nve"_fix_nve.html, "fix langevin"_fix_langevin.html, "fix nve/dot"_fix_nve_dot.html, "bond_style oxdna/fene"_bond_oxdna.html, "bond_style oxdna2/fene"_bond_oxdna.html, "pair_style oxdna/excv"_pair_oxdna.html, "pair_style oxdna2/excv"_pair_oxdna2.html
[Default:] none
:line
:link(Davidchack2)
[(Davidchack)] R.L Davidchack, T.E. Ouldridge, M.V. Tretyakov. J. Chem. Phys. 142, 144114 (2015).
:link(Miller2)
[(Miller)] T. F. Miller III, M. Eleftheriou, P. Pattnaik, A. Ndirango, G. J. Martyna, J. Chem. Phys., 116, 8649-8659 (2002).
:link(Dunweg3)
[(Dunweg)] B. Dunweg, W. Paul, Int. J. Mod. Phys. C, 2, 817-27 (1991).
:link(Henrich4)
[(Henrich)] O. Henrich, Y. A. Gutierrez-Fosado, T. Curk, T. E. Ouldridge, Eur. Phys. J. E 41, 57 (2018).

402
doc/txt/pair_meamc.txt
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@ -1,402 +0,0 @@
"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 meam/c command :h3
[Syntax:]
pair_style style :pre
style = {meam/c}
[Examples:]
pair_style meam/c
pair_coeff * * ../potentials/library.meam Si ../potentials/si.meam Si
pair_coeff * * ../potentials/library.meam Ni Al NULL Ni Al Ni Ni :pre
[Description:]
NOTE: The behavior of the MEAM potential for alloy systems has changed
as of November 2010; see description below of the mixture_ref_t
parameter
Style {meam/c} computes pairwise interactions for a variety of materials
using modified embedded-atom method (MEAM) potentials
"(Baskes)"_#Baskes. Conceptually, it is an extension to the original
"EAM potentials"_pair_eam.html which adds angular forces. It is
thus suitable for modeling metals and alloys with fcc, bcc, hcp and
diamond cubic structures, as well as covalently bonded materials like
silicon and carbon. Style {meam/c} is a translation of the (now obsolete)
{meam} code from Fortran to C++. It is functionally equivalent to {meam}
but more efficient, and thus {meam} has been removed from LAMMPS after
the 12 December 2018 release.
In the MEAM formulation, the total energy E of a system of atoms is
given by:
:c,image(Eqs/pair_meam.jpg)
where F is the embedding energy which is a function of the atomic
electron density rho, and phi is a pair potential interaction. The
pair interaction is summed over all neighbors J of atom I within the
cutoff distance. As with EAM, the multi-body nature of the MEAM
potential is a result of the embedding energy term. Details of the
computation of the embedding and pair energies, as implemented in
LAMMPS, are given in "(Gullet)"_#Gullet and references therein.
The various parameters in the MEAM formulas are listed in two files
which are specified by the "pair_coeff"_pair_coeff.html command.
These are ASCII text files in a format consistent with other MD codes
that implement MEAM potentials, such as the serial DYNAMO code and
Warp. Several MEAM potential files with parameters for different
materials are included in the "potentials" directory of the LAMMPS
distribution with a ".meam" suffix. All of these are parameterized in
terms of LAMMPS "metal units"_units.html.
Note that unlike for other potentials, cutoffs for MEAM potentials are
not set in the pair_style or pair_coeff command; they are specified in
the MEAM potential files themselves.
Only a single pair_coeff command is used with the {meam} style which
specifies two MEAM files and the element(s) to extract information
for. The MEAM elements are mapped to LAMMPS atom types by specifying
N additional arguments after the 2nd filename in the pair_coeff
command, where N is the number of LAMMPS atom types:
MEAM library file
Elem1, Elem2, ...
MEAM parameter file
N element names = mapping of MEAM elements to atom types :ul
See the "pair_coeff"_pair_coeff.html doc page for alternate ways
to specify the path for the potential files.
As an example, the potentials/library.meam file has generic MEAM
settings for a variety of elements. The potentials/SiC.meam file has
specific parameter settings for a Si and C alloy system. If your
LAMMPS simulation has 4 atoms types and you want the 1st 3 to be Si,
and the 4th to be C, you would use the following pair_coeff command:
pair_coeff * * library.meam Si C sic.meam Si Si Si C :pre
The 1st 2 arguments must be * * so as to span all LAMMPS atom types.
The two filenames are for the library and parameter file respectively.
The Si and C arguments (between the file names) are the two elements
for which info will be extracted from the library file. The first
three trailing Si arguments map LAMMPS atom types 1,2,3 to the MEAM Si
element. The final C argument maps LAMMPS atom type 4 to the MEAM C
element.
If the 2nd filename is specified as NULL, no parameter file is read,
which simply means the generic parameters in the library file are
used. Use of the NULL specification for the parameter file is
discouraged for systems with more than a single element type
(e.g. alloys), since the parameter file is expected to set element
interaction terms that are not captured by the information in the
library file.
If a mapping value is specified as NULL, the mapping is not performed.
This can be used when a {meam} potential is used as part of the
{hybrid} pair style. The NULL values are placeholders for atom types
that will be used with other potentials.
NOTE: If the 2nd filename is NULL, the element names between the two
filenames can appear in any order, e.g. "Si C" or "C Si" in the
example above. However, if the 2nd filename is not NULL (as in the
example above), it contains settings that are Fortran-indexed for the
elements that preceed it. Thus you need to insure you list the
elements between the filenames in an order consistent with how the
values in the 2nd filename are indexed. See details below on the
syntax for settings in the 2nd file.
The MEAM library file provided with LAMMPS has the name
potentials/library.meam. It is the "meamf" file used by other MD
codes. Aside from blank and comment lines (start with #) which can
appear anywhere, it is formatted as a series of entries, each of which
has 19 parameters and can span multiple lines:
elt, lat, z, ielement, atwt, alpha, b0, b1, b2, b3, alat, esub, asub,
t0, t1, t2, t3, rozero, ibar
The "elt" and "lat" parameters are text strings, such as elt = Si or
Cu and lat = dia or fcc. Because the library file is used by Fortran
MD codes, these strings may be enclosed in single quotes, but this is
not required. The other numeric parameters match values in the
formulas above. The value of the "elt" string is what is used in the
pair_coeff command to identify which settings from the library file
you wish to read in. There can be multiple entries in the library
file with the same "elt" value; LAMMPS reads the 1st matching entry it
finds and ignores the rest.
Other parameters in the MEAM library file correspond to single-element
potential parameters:
lat = lattice structure of reference configuration
z = number of nearest neighbors in the reference structure
This field is only read for compatibility, the correct
value is inferred from the lattice structure
ielement = atomic number
atwt = atomic weight
alat = lattice constant of reference structure
esub = energy per atom (eV) in the reference structure at equilibrium
asub = "A" parameter for MEAM (see e.g. "(Baskes)"_#Baskes) :pre
The alpha, b0, b1, b2, b3, t0, t1, t2, t3 parameters correspond to the
standard MEAM parameters in the literature "(Baskes)"_#Baskes (the b
parameters are the standard beta parameters). Note that only parameters
normalized to t0 = 1.0 are supported. The rozero parameter is
an element-dependent density scaling that weights the reference
background density (see e.g. equation 4.5 in "(Gullet)"_#Gullet) and
is typically 1.0 for single-element systems. The ibar parameter
selects the form of the function G(Gamma) used to compute the electron
density; options are
0 => G = sqrt(1+Gamma)
1 => G = exp(Gamma/2)
2 => not implemented
3 => G = 2/(1+exp(-Gamma))
4 => G = sqrt(1+Gamma)
-5 => G = +-sqrt(abs(1+Gamma)) :pre
If used, the MEAM parameter file contains settings that override or
complement the library file settings. Examples of such parameter
files are in the potentials directory with a ".meam" suffix. Their
format is the same as is read by other Fortran MD codes. Aside from
blank and comment lines (start with #) which can appear anywhere, each
line has one of the following forms. Each line can also have a
trailing comment (starting with #) which is ignored.
keyword = value
keyword(I) = value
keyword(I,J) = value
keyword(I,J,K) = value :pre
The indices I, J, K correspond to the elements selected from the
MEAM library file numbered in the order of how those elements were
selected starting from 1. Thus for the example given below
pair_coeff * * library.meam Si C sic.meam Si Si Si C :pre
an index of 1 would refer to Si and an index of 2 to C.
The recognized keywords for the parameter file are as follows:
Ec, alpha, rho0, delta, lattce, attrac, repuls, nn2, Cmin, Cmax, rc, delr,
augt1, gsmooth_factor, re
where
rc = cutoff radius for cutoff function; default = 4.0
delr = length of smoothing distance for cutoff function; default = 0.1
rho0(I) = relative density for element I (overwrites value
read from meamf file)
Ec(I,J) = cohesive energy of reference structure for I-J mixture
delta(I,J) = heat of formation for I-J alloy; if Ec_IJ is input as
zero, then LAMMPS sets Ec_IJ = (Ec_II + Ec_JJ)/2 - delta_IJ
alpha(I,J) = alpha parameter for pair potential between I and J (can
be computed from bulk modulus of reference structure
re(I,J) = equilibrium distance between I and J in the reference
structure
Cmax(I,J,K) = Cmax screening parameter when I-J pair is screened
by K (I<=J); default = 2.8
Cmin(I,J,K) = Cmin screening parameter when I-J pair is screened
by K (I<=J); default = 2.0
lattce(I,J) = lattice structure of I-J reference structure:
dia = diamond (interlaced fcc for alloy)
fcc = face centered cubic
bcc = body centered cubic
dim = dimer
b1 = rock salt (NaCl structure)
hcp = hexagonal close-packed
c11 = MoSi2 structure
l12 = Cu3Au structure (lower case L, followed by 12)
b2 = CsCl structure (interpenetrating simple cubic)
nn2(I,J) = turn on second-nearest neighbor MEAM formulation for
I-J pair (see for example "(Lee)"_#Lee).
0 = second-nearest neighbor formulation off
1 = second-nearest neighbor formulation on
default = 0
attrac(I,J) = additional cubic attraction term in Rose energy I-J pair potential
default = 0
repuls(I,J) = additional cubic repulsive term in Rose energy I-J pair potential
default = 0
zbl(I,J) = blend the MEAM I-J pair potential with the ZBL potential for small
atom separations "(ZBL)"_#ZBL
default = 1
gsmooth_factor = factor determining the length of the G-function smoothing
region; only significant for ibar=0 or ibar=4.
99.0 = short smoothing region, sharp step
0.5 = long smoothing region, smooth step
default = 99.0
augt1 = integer flag for whether to augment t1 parameter by
3/5*t3 to account for old vs. new meam formulations;
0 = don't augment t1
1 = augment t1
default = 1
ialloy = integer flag to use alternative averaging rule for t parameters,
for comparison with the DYNAMO MEAM code
0 = standard averaging (matches ialloy=0 in DYNAMO)
1 = alternative averaging (matches ialloy=1 in DYNAMO)
2 = no averaging of t (use single-element values)
default = 0
mixture_ref_t = integer flag to use mixture average of t to compute the background
reference density for alloys, instead of the single-element values
(see description and warning elsewhere in this doc page)
0 = do not use mixture averaging for t in the reference density
1 = use mixture averaging for t in the reference density
default = 0
erose_form = integer value to select the form of the Rose energy function
(see description below).
default = 0
emb_lin_neg = integer value to select embedding function for negative densities
0 = F(rho)=0
1 = F(rho) = -asub*esub*rho (linear in rho, matches DYNAMO)
default = 0
bkgd_dyn = integer value to select background density formula
0 = rho_bkgd = rho_ref_meam(a) (as in the reference structure)
1 = rho_bkgd = rho0_meam(a)*Z_meam(a) (matches DYNAMO)
default = 0 :pre
Rc, delr, re are in distance units (Angstroms in the case of metal
units). Ec and delta are in energy units (eV in the case of metal
units).
Each keyword represents a quantity which is either a scalar, vector,
2d array, or 3d array and must be specified with the correct
corresponding array syntax. The indices I,J,K each run from 1 to N
where N is the number of MEAM elements being used.
Thus these lines
rho0(2) = 2.25
alpha(1,2) = 4.37 :pre
set rho0 for the 2nd element to the value 2.25 and set alpha for the
alloy interaction between elements 1 and 2 to 4.37.
The augt1 parameter is related to modifications in the MEAM
formulation of the partial electron density function. In recent
literature, an extra term is included in the expression for the
third-order density in order to make the densities orthogonal (see for
example "(Wang)"_#Wang2, equation 3d); this term is included in the
MEAM implementation in lammps. However, in earlier published work
this term was not included when deriving parameters, including most of
those provided in the library.meam file included with lammps, and to
account for this difference the parameter t1 must be augmented by
3/5*t3. If augt1=1, the default, this augmentation is done
automatically. When parameter values are fit using the modified
density function, as in more recent literature, augt1 should be set to
0.
The mixture_ref_t parameter is available to match results with those
of previous versions of lammps (before January 2011). Newer versions
of lammps, by default, use the single-element values of the t
parameters to compute the background reference density. This is the
proper way to compute these parameters. Earlier versions of lammps
used an alloy mixture averaged value of t to compute the background
reference density. Setting mixture_ref_t=1 gives the old behavior.
WARNING: using mixture_ref_t=1 will give results that are demonstrably
incorrect for second-neighbor MEAM, and non-standard for
first-neighbor MEAM; this option is included only for matching with
previous versions of lammps and should be avoided if possible.
The parameters attrac and repuls, along with the integer selection
parameter erose_form, can be used to modify the Rose energy function
used to compute the pair potential. This function gives the energy of
the reference state as a function of interatomic spacing. The form of
this function is:
astar = alpha * (r/re - 1.d0)
if erose_form = 0: erose = -Ec*(1+astar+a3*(astar**3)/(r/re))*exp(-astar)
if erose_form = 1: erose = -Ec*(1+astar+(-attrac+repuls/r)*(astar**3))*exp(-astar)
if erose_form = 2: erose = -Ec*(1 +astar + a3*(astar**3))*exp(-astar)
a3 = repuls, astar < 0
a3 = attrac, astar >= 0 :pre
Most published MEAM parameter sets use the default values attrac=repulse=0.
Setting repuls=attrac=delta corresponds to the form used in several
recent published MEAM parameter sets, such as "(Valone)"_#Valone
NOTE: The default form of the erose expression in LAMMPS was corrected
in March 2009. The current version is correct, but may show different
behavior compared with earlier versions of lammps with the attrac
and/or repuls parameters are non-zero. To obtain the previous default
form, use erose_form = 1 (this form does not seem to appear in the
literature). An alternative form (see e.g. "(Lee2)"_#Lee2) is
available using erose_form = 2.
:line
[Mixing, shift, table, tail correction, restart, rRESPA info]:
For atom type pairs I,J and I != J, where types I and J correspond to
two different element types, mixing is performed by LAMMPS with
user-specifiable parameters as described above. You never need to
specify a pair_coeff command with I != J arguments for this style.
This pair style does not support the "pair_modify"_pair_modify.html
shift, table, and tail options.
This pair style does not write its information to "binary restart
files"_restart.html, since it is stored in potential files. Thus, you
need to re-specify the pair_style and pair_coeff commands in an input
script that reads a restart file.
This pair style can only be used via the {pair} keyword of the
"run_style respa"_run_style.html command. It does not support the
{inner}, {middle}, {outer} keywords.
:line
[Restrictions:]
The {meam/c} style is provided in the USER-MEAMC package. It is
only enabled if LAMMPS was built with that package.
See the "Build package"_Build_package.html doc page for more info.
The maximum number of elements, that can be read from the MEAM
library file, is determined at compile time. The default is 5.
If you need support for more elements, you have to change the
define for the constant 'maxelt' at the beginning of the file
src/USER-MEAMC/meam.h and update/recompile LAMMPS. There is no
limit on the number of atoms types.
[Related commands:]
"pair_coeff"_pair_coeff.html, "pair_style eam"_pair_eam.html,
"pair_style meam/spline"_pair_meam_spline.html
[Default:] none
:line
:link(Baskes)
[(Baskes)] Baskes, Phys Rev B, 46, 2727-2742 (1992).
:link(Gullet)
[(Gullet)] Gullet, Wagner, Slepoy, SANDIA Report 2003-8782 (2003).
This report may be accessed on-line via "this link"_sandreport.
:link(sandreport,http://infoserve.sandia.gov/sand_doc/2003/038782.pdf)
:link(Lee)
[(Lee)] Lee, Baskes, Phys. Rev. B, 62, 8564-8567 (2000).
:link(Lee2)
[(Lee2)] Lee, Baskes, Kim, Cho. Phys. Rev. B, 64, 184102 (2001).
:link(Valone)
[(Valone)] Valone, Baskes, Martin, Phys. Rev. B, 73, 214209 (2006).
:link(Wang2)
[(Wang)] Wang, Van Hove, Ross, Baskes, J. Chem. Phys., 121, 5410 (2004).
:link(ZBL)
[(ZBL)] J.F. Ziegler, J.P. Biersack, U. Littmark, "Stopping and Ranges
of Ions in Matter", Vol 1, 1985, Pergamon Press.

112
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@ -1,112 +0,0 @@
"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 oxdna/excv command :h3
pair_style oxdna/stk command :h3
pair_style oxdna/hbond command :h3
pair_style oxdna/xstk command :h3
pair_style oxdna/coaxstk command :h3
[Syntax:]
pair_style style1 :pre
pair_coeff * * style2 args :pre
style1 = {hybrid/overlay oxdna/excv oxdna/stk oxdna/hbond oxdna/xstk oxdna/coaxstk} :ul
style2 = {oxdna/excv} or {oxdna/stk} or {oxdna/hbond} or {oxdna/xstk} or {oxdna/coaxstk}
args = list of arguments for these particular styles :ul
{oxdna/stk} args = seq T xi kappa 6.0 0.4 0.9 0.32 0.75 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
{oxdna/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 = 1.077 (between base pairs A-T and C-G) or 0 (all other pairs) :pre
[Examples:]
pair_style hybrid/overlay oxdna/excv oxdna/stk oxdna/hbond oxdna/xstk oxdna/coaxstk
pair_coeff * * oxdna/excv 2.0 0.7 0.675 2.0 0.515 0.5 2.0 0.33 0.32
pair_coeff * * oxdna/stk seqdep 0.1 1.3448 2.6568 6.0 0.4 0.9 0.32 0.75 1.3 0 0.8 0.9 0 0.95 0.9 0 0.95 2.0 0.65 2.0 0.65
pair_coeff * * oxdna/hbond seqdep 0.0 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
pair_coeff 1 4 oxdna/hbond seqdep 1.077 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
pair_coeff 2 3 oxdna/hbond seqdep 1.077 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
pair_coeff * * oxdna/xstk 47.5 0.575 0.675 0.495 0.655 2.25 0.791592653589793 0.58 1.7 1.0 0.68 1.7 1.0 0.68 1.5 0 0.65 1.7 0.875 0.68 1.7 0.875 0.68
pair_coeff * * oxdna/coaxstk 46.0 0.4 0.6 0.22 0.58 2.0 2.541592653589793 0.65 1.3 0 0.8 0.9 0 0.95 0.9 0 0.95 2.0 -0.65 2.0 -0.65 :pre
[Description:]
The {oxdna} pair styles compute the pairwise-additive parts of the oxDNA force field
for coarse-grained modelling of DNA. The effective interaction between the nucleotides consists of potentials for the
excluded volume interaction {oxdna/excv}, the stacking {oxdna/stk}, cross-stacking {oxdna/xstk}
and coaxial stacking interaction {oxdna/coaxstk} as well
as the hydrogen-bonding interaction {oxdna/hbond} between complementary pairs of nucleotides on
opposite strands. Average sequence or sequence-dependent stacking and base-pairing strengths
are supported "(Sulc)"_#Sulc1. Quasi-unique base-pairing between nucleotides can be achieved by using
more complementary pairs of atom types like 5-8 and 6-7, 9-12 and 10-11, 13-16 and 14-15, etc.
This prevents the hybridization of in principle complementary bases within Ntypes/4 bases
up and down along the backbone.
The exact functional form of the pair styles is rather complex.
The individual potentials consist of products of modulation factors,
which themselves are constructed from a number of more basic potentials
(Morse, Lennard-Jones, harmonic angle and distance) as well as quadratic smoothing and modulation terms.
We refer to "(Ouldridge-DPhil)"_#Ouldridge-DPhil1 and "(Ouldridge)"_#Ouldridge1
for a detailed description of the oxDNA force field.
NOTE: These pair styles have to be used together with the related oxDNA bond style
{oxdna/fene} for the connectivity of the phosphate backbone (see also documentation of
"bond_style oxdna/fene"_bond_oxdna.html). Most of the coefficients
in the above example have to be kept fixed and cannot be changed without reparameterizing the entire model.
Exceptions are the first four coefficients after {oxdna/stk} (seq=seqdep, T=0.1, xi=1.3448 and kappa=2.6568 in the above example)
and the first coefficient after {oxdna/hbond} (seq=seqdep in the above example).
When using a Langevin thermostat, e.g. through "fix langevin"_fix_langevin.html
or "fix nve/dotc/langevin"_fix_nve_dotc_langevin.html
the temperature coefficients have to be matched to the one used in the fix.
Example input and data files for DNA duplexes can be found in examples/USER/cgdna/examples/oxDNA/ and /oxDNA2/.
A simple python setup tool which creates single straight or helical DNA strands,
DNA duplexes or arrays of DNA duplexes can be found in examples/USER/cgdna/util/.
Please cite "(Henrich)"_#Henrich1 and the relevant oxDNA articles in any publication that uses this implementation.
The article contains more information on the model, the structure of the input file, the setup tool
and the performance of the LAMMPS-implementation of oxDNA.
The preprint version of the article can be found "here"_PDF/USER-CGDNA.pdf.
:line
[Restrictions:]
These pair styles can only be used if LAMMPS was built with the
USER-CGDNA package and the MOLECULE and ASPHERE package. See the
"Build package"_Build_package.html doc page for more info.
[Related commands:]
"bond_style oxdna/fene"_bond_oxdna.html, "fix nve/dotc/langevin"_fix_nve_dotc_langevin.html, "pair_coeff"_pair_coeff.html,
"bond_style oxdna2/fene"_bond_oxdna.html, "pair_style oxdna2/excv"_pair_oxdna2.html
[Default:] none
:line
:link(Henrich1)
[(Henrich)] O. Henrich, Y. A. Gutierrez-Fosado, T. Curk, T. E. Ouldridge, Eur. Phys. J. E 41, 57 (2018).
:link(Sulc1)
[(Sulc)] P. Sulc, F. Romano, T.E. Ouldridge, L. Rovigatti, J.P.K. Doye, A.A. Louis, J. Chem. Phys. 137, 135101 (2012).
:link(Ouldridge-DPhil1)
[(Ouldrigde-DPhil)] T.E. Ouldridge, Coarse-grained modelling of DNA and DNA self-assembly, DPhil. University of Oxford (2011).
:link(Ouldridge1)
[(Ouldridge)] T.E. Ouldridge, A.A. Louis, J.P.K. Doye, J. Chem. Phys. 134, 085101 (2011).

121
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"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 oxdna2/excv command :h3
pair_style oxdna2/stk command :h3
pair_style oxdna2/hbond command :h3
pair_style oxdna2/xstk command :h3
pair_style oxdna2/coaxstk command :h3
pair_style oxdna2/dh command :h3
[Syntax:]
pair_style style1 :pre
pair_coeff * * style2 args :pre
style1 = {hybrid/overlay oxdna2/excv oxdna2/stk oxdna2/hbond oxdna2/xstk oxdna2/coaxstk oxdna2/dh} :ul
style2 = {oxdna2/excv} or {oxdna2/stk} or {oxdna2/hbond} or {oxdna2/xstk} or {oxdna2/coaxstk} or {oxdna2/dh}
args = list of arguments for these particular styles :ul
{oxdna2/stk} args = seq T xi kappa 6.0 0.4 0.9 0.32 0.75 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
{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)
{oxdna2/dh} args = T rhos qeff
T = temperature (oxDNA units, 0.1 = 300 K)
rhos = salt concentration (mole per litre)
qeff = effective charge (elementary charges) :pre
[Examples:]
pair_style hybrid/overlay oxdna2/excv oxdna2/stk oxdna2/hbond oxdna2/xstk oxdna2/coaxstk oxdna2/dh
pair_coeff * * oxdna2/excv 2.0 0.7 0.675 2.0 0.515 0.5 2.0 0.33 0.32
pair_coeff * * oxdna2/stk seqdep 0.1 1.3523 2.6717 6.0 0.4 0.9 0.32 0.75 1.3 0 0.8 0.9 0 0.95 0.9 0 0.95 2.0 0.65 2.0 0.65
pair_coeff * * oxdna2/hbond seqdep 0.0 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
pair_coeff 1 4 oxdna2/hbond seqdep 1.0678 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
pair_coeff 2 3 oxdna2/hbond seqdep 1.0678 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
pair_coeff * * oxdna2/xstk 47.5 0.575 0.675 0.495 0.655 2.25 0.791592653589793 0.58 1.7 1.0 0.68 1.7 1.0 0.68 1.5 0 0.65 1.7 0.875 0.68 1.7 0.875 0.68
pair_coeff * * oxdna2/coaxstk 58.5 0.4 0.6 0.22 0.58 2.0 2.891592653589793 0.65 1.3 0 0.8 0.9 0 0.95 0.9 0 0.95 40.0 3.116592653589793
pair_coeff * * oxdna2/dh 0.1 1.0 0.815 :pre
[Description:]
The {oxdna2} pair styles compute the pairwise-additive parts of the oxDNA force field
for coarse-grained modelling of DNA. The effective interaction between the nucleotides consists of potentials for the
excluded volume interaction {oxdna2/excv}, the stacking {oxdna2/stk}, cross-stacking {oxdna2/xstk}
and coaxial stacking interaction {oxdna2/coaxstk}, electrostatic Debye-Hueckel interaction {oxdna2/dh}
as well as the hydrogen-bonding interaction {oxdna2/hbond} between complementary pairs of nucleotides on
opposite strands. Average sequence or sequence-dependent stacking and base-pairing strengths
are supported "(Sulc)"_#Sulc2. Quasi-unique base-pairing between nucleotides can be achieved by using
more complementary pairs of atom types like 5-8 and 6-7, 9-12 and 10-11, 13-16 and 14-15, etc.
This prevents the hybridization of in principle complementary bases within Ntypes/4 bases
up and down along the backbone.
The exact functional form of the pair styles is rather complex.
The individual potentials consist of products of modulation factors,
which themselves are constructed from a number of more basic potentials
(Morse, Lennard-Jones, harmonic angle and distance) as well as quadratic smoothing and modulation terms.
We refer to "(Snodin)"_#Snodin and the original oxDNA publications "(Ouldridge-DPhil)"_#Ouldridge-DPhil2
and "(Ouldridge)"_#Ouldridge2 for a detailed description of the oxDNA2 force field.
NOTE: These pair styles have to be used together with the related oxDNA2 bond style
{oxdna2/fene} for the connectivity of the phosphate backbone (see also documentation of
"bond_style oxdna2/fene"_bond_oxdna.html). Most of the coefficients
in the above example have to be kept fixed and cannot be changed without reparameterizing the entire model.
Exceptions are the first four coefficients after {oxdna2/stk} (seq=seqdep, T=0.1, xi=1.3523 and kappa=2.6717 in the above example),
the first coefficient after {oxdna2/hbond} (seq=seqdep in the above example) and the three coefficients
after {oxdna2/dh} (T=0.1, rhos=1.0, qeff=0.815 in the above example). When using a Langevin thermostat
e.g. through "fix langevin"_fix_langevin.html or "fix nve/dotc/langevin"_fix_nve_dotc_langevin.html
the temperature coefficients have to be matched to the one used in the fix.
Example input and data files for DNA duplexes can be found in examples/USER/cgdna/examples/oxDNA/ and /oxDNA2/.
A simple python setup tool which creates single straight or helical DNA strands,
DNA duplexes or arrays of DNA duplexes can be found in examples/USER/cgdna/util/.
Please cite "(Henrich)"_#Henrich and the relevant oxDNA articles in any publication that uses this implementation.
The article contains more information on the model, the structure of the input file, the setup tool
and the performance of the LAMMPS-implementation of oxDNA.
The preprint version of the article can be found "here"_PDF/USER-CGDNA.pdf.
:line
[Restrictions:]
These pair styles can only be used if LAMMPS was built with the
USER-CGDNA package and the MOLECULE and ASPHERE package. See the
"Build package"_Build_package.html doc page for more info.
[Related commands:]
"bond_style oxdna2/fene"_bond_oxdna.html, "fix nve/dotc/langevin"_fix_nve_dotc_langevin.html, "pair_coeff"_pair_coeff.html,
"bond_style oxdna/fene"_bond_oxdna.html, "pair_style oxdna/excv"_pair_oxdna.html
[Default:] none
:line
:link(Henrich)
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3
examples/README
View File

@ -164,6 +164,9 @@ The MC directory has an example script for using LAMMPS as an
energy-evaluation engine in a iterative Monte Carlo energy-relaxation
loop.
The TIP4P directory has an example for testing forces computed on a
GPU.
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