Added fix nphug docs
git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@6918 f3b2605a-c512-4ea7-a41b-209d697bcdaa
This commit is contained in:
athomps
@ -155,7 +155,7 @@ all.
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</P>
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<P><B>Related commands:</B>
|
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</P>
|
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<P><A HREF = "fix_deform.html">fix deform</A>
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<P><A HREF = "fix_nphug.html">fix nphug</A>, <A HREF = "fix_deform.html">fix deform</A>
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</P>
|
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<P><B>Default:</B>
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</P>
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|
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@ -145,7 +145,7 @@ all.
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|
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[Related commands:]
|
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|
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"fix deform"_fix_deform.html
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"fix nphug"_fix_nphug.html, "fix deform"_fix_deform.html
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|
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[Default:]
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|
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|
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@ -28,7 +28,7 @@
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<LI>style_name = <I>nvt</I> or <I>npt</I> or <I>nph</I>
|
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|
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<PRE>one or more keyword value pairs may be appended
|
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keyword = <I>temp</I> or <I>iso</I> or <I>aniso</I> or <I>tri</I> or <I>x</I> or <I>y</I> or <I>z</I> or <I>xy</I> or <I>yz</I> or <I>xz</I> or <I>couple</I> or <I>tchain</I> or <I>pchain</I> or <I>mtk</I> or <I>tloop</I> or <I>ploop</I> or <I>nreset</I> or <I>drag</I> or <I>dilate</I>
|
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keyword = <I>temp</I> or <I>iso</I> or <I>aniso</I> or <I>tri</I> or <I>x</I> or <I>y</I> or <I>z</I> or <I>xy</I> or <I>yz</I> or <I>xz</I> or <I>couple</I> or <I>tchain</I> or <I>pchain</I> or <I>mtk</I> or <I>tloop</I> or <I>ploop</I> or <I>nreset</I> or <I>drag</I> or <I>dilate</I> or <I>scaleyz</I> or <I>scalexz</I> or <I>scalexy</I>
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<I>temp</I> values = Tstart Tstop Tdamp
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Tstart,Tstop = external temperature at start/end of run
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Tdamp = temperature damping parameter (time units)
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@ -19,7 +19,7 @@ fix ID group-ID style_name keyword value ... :pre
|
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ID, group-ID are documented in "fix"_fix.html command :ulb,l
|
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style_name = {nvt} or {npt} or {nph} :l
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one or more keyword value pairs may be appended
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keyword = {temp} or {iso} or {aniso} or {tri} or {x} or {y} or {z} or {xy} or {yz} or {xz} or {couple} or {tchain} or {pchain} or {mtk} or {tloop} or {ploop} or {nreset} or {drag} or {dilate}
|
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keyword = {temp} or {iso} or {aniso} or {tri} or {x} or {y} or {z} or {xy} or {yz} or {xz} or {couple} or {tchain} or {pchain} or {mtk} or {tloop} or {ploop} or {nreset} or {drag} or {dilate} or {scaleyz} or {scalexz} or {scalexy}
|
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{temp} values = Tstart Tstop Tdamp
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Tstart,Tstop = external temperature at start/end of run
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Tdamp = temperature damping parameter (time units)
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219
doc/fix_nphug.html
Normal file
219
doc/fix_nphug.html
Normal file
@ -0,0 +1,219 @@
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<HTML>
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<CENTER><A HREF = "http://lammps.sandia.gov">LAMMPS WWW Site</A> - <A HREF = "Manual.html">LAMMPS Documentation</A> - <A HREF = "Section_commands.html#comm">LAMMPS Commands</A>
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</CENTER>
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<HR>
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<H3>fix nphug command
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</H3>
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<P><B>Syntax:</B>
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</P>
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<PRE>fix ID group-ID nphug keyword value ...
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</PRE>
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<UL><LI>ID, group-ID are documented in <A HREF = "fix.html">fix</A> command
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<PRE>one or more keyword value pairs may be appended
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keyword = <I>temp</I> or <I>iso</I> or <I>aniso</I> or <I>tri</I> or <I>x</I> or <I>y</I> or <I>z</I> or <I>couple</I> or <I>tchain</I> or <I>pchain</I> or <I>mtk</I> or <I>tloop</I> or <I>ploop</I> or <I>nreset</I> or <I>drag</I> or <I>dilate</I> or <I>scaleyz</I> or <I>scalexz</I> or <I>scalexy</I>
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<I>temp</I> values = Value1 Value2 Tdamp
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Value1, Value2 = Nose-Hoover target temperatures, ignored by Hugoniostat
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Tdamp = temperature damping parameter (time units)
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<I>iso</I> or <I>aniso</I> or <I>tri</I> values = Pstart Pstop Pdamp
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Pstart,Pstop = scalar external pressures, must be equal (pressure units)
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Pdamp = pressure damping parameter (time units)
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<I>x</I> or <I>y</I> or <I>z</I> or <I>xy</I> or <I>yz</I> or <I>xz</I> values = Pstart Pstop Pdamp
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Pstart,Pstop = external stress tensor components, must be equal (pressure units)
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Pdamp = stress damping parameter (time units)
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<I>couple</I> = <I>none</I> or <I>xyz</I> or <I>xy</I> or <I>yz</I> or <I>xz</I>
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<I>tchain</I> value = length of thermostat chain (1 = single thermostat)
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<I>pchain</I> values = length of thermostat chain on barostat (0 = no thermostat)
|
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<I>mtk</I> value = <I>yes</I> or <I>no</I> = add in MTK adjustment term or not
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<I>tloop</I> value = number of sub-cycles to perform on thermostat
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<I>ploop</I> value = number of sub-cycles to perform on barostat thermostat
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<I>nreset</I> value = reset reference cell every this many timesteps
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<I>drag</I> value = drag factor added to barostat/thermostat (0.0 = no drag)
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<I>dilate</I> value = <I>all</I> or <I>partial</I>
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<I>scaleyz</I> value = <I>yes</I> or <I>no</I> = scale yz with lz
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<I>scalexz</I> value = <I>yes</I> or <I>no</I> = scale xz with lz
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<I>scalexy</I> value = <I>yes</I> or <I>no</I> = scale xy with ly
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</PRE>
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</UL>
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<P><B>Examples:</B>
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</P>
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<P>fix myhug all nphug temp 1.0 1.0 10.0 z 40.0 40.0 70.0
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fix myhug all nphug temp 1.0 1.0 10.0 iso 40.0 40.0 70.0 drag 200.0 tchain 1 pchain 0
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</P>
|
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<P><B>Description:</B>
|
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</P>
|
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<P>This command is a variant of the Nose-Hoover
|
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<A HREF = "fix_nh.html">fix npt</A> fix style.
|
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It performs time integration of the Hugoniostat equations
|
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of motion developed by Ravelo et al. <A HREF = "#Ravelo">(Ravelo)</A>.
|
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These equations compress the system to a state with average
|
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axial stress or pressure equal to the specified target value
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||||
and that satisfies the Rankine-Hugoniot (RH)
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jump conditions for steady shocks.
|
||||
</P>
|
||||
<P>The compression can be performed
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either
|
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hydrostatically (using keyword iso, aniso, or tri) or uniaxially
|
||||
(using keywords x, y, or z). In the hydrostatic case,
|
||||
the cell dimensions change dynamically so that the average axial stress
|
||||
in all three directions converges towards the specified target value.
|
||||
In the uniaxial case, the chosen cell dimension changes dynamically
|
||||
so that the average
|
||||
axial stress in that direction converges towards the target value. The
|
||||
other two cell dimensions are kept fixed (zero lateral strain).
|
||||
</P>
|
||||
<P>This leads to the following additional restrictions on the keywords:
|
||||
</P>
|
||||
<P>One and only one of the following keywords should be used: iso, aniso, tri, x, y, z,
|
||||
</P>
|
||||
<P>The specified initial and final target pressures must be the same.
|
||||
</P>
|
||||
<P>The keywords xy, xz, yz may not be used.
|
||||
</P>
|
||||
<P>The only admissible value for the couple keyword is xyz,
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which has the same effect as keyword iso
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</P>
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<UL><LI>The temp keyword must be used in order to specify the time constant for
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<LI>kinetic energy relaxation, but initial and final target temperature values
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<LI>are ignored.
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</UL>
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<P>Essentially, a Hugoniostat simulation is an NPT simulation in which the
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user-specified target temperature is replaced with a time-dependent
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target temperature Tt obtained from the following equation:
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</P>
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<P>Tt - T = (0.5*(P+P0)(V0-V)+E0-E)/(Ndof kB) = Delta
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</P>
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<P>where T and Tt are the instantaneous and target temperatures,
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P and P0 are the instantaneous and reference pressure or axial stress,
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depending on whether hydrostatic or uniaxial compression is being
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performed, V and V0 are the instantaneous and reference volumes,
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E and E0 are the instantaneous and reference internal energy (potential
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plus kinetic), Ndof is the number of degrees of freedom used in the
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definition of temperature, and kB is the Boltzmann constant. Delta is the
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negative deviation of the instantaneous temperature from the target temperature.
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The values of E0, V0, and P0 are the instantaneous values at the start of
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the simulation. These can be overridden using the fix_modify keywords <I>e0</I>,
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<I>v0</I>, and <I>p0</I> described below.
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</P>
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<HR>
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<P>IMPORTANT NOTE: Unlike the <A HREF = "fix_temp_berendsen.html">fix
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temp/berendsen</A> command which performs
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thermostatting but NO time integration, this fix performs
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thermostatting/barostatting AND time integration. Thus you should not
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use any other time integration fix, such as <A HREF = "fix_nve.html">fix nve</A> on
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atoms to which this fix is applied. Likewise, this fix should not be
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used on atoms that have their temperature controlled by another fix
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- e.g. by <A HREF = "fix_nh.html">fix langevin</A> or <A HREF = "fix_temp_rescale.html">fix temp/rescale</A>
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commands.
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</P>
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<HR>
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<P>This fix compute a temperature and pressure each timestep. To do
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this, the fix creates its own computes of style "temp" and "pressure",
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as if one of these two sets of commands had been issued:
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</P>
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<PRE>compute fix-ID_temp group-ID temp
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compute fix-ID_press group-ID pressure fix-ID_temp
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</PRE>
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<PRE>compute fix-ID_temp all temp
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compute fix-ID_press all pressure fix-ID_temp
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</PRE>
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<P>See the <A HREF = "compute_temp.html">compute temp</A> and <A HREF = "compute_pressure.html">compute
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pressure</A> commands for details. Note that the
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IDs of the new computes are the fix-ID + underscore + "temp" or fix_ID
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+ underscore + "press". For fix nvt, the group for the new computes
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is the same as the fix group. For fix nph and fix npt, the group for
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the new computes is "all" since pressure is computed for the entire
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system.
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</P>
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<P>Note that these are NOT the computes used by thermodynamic output (see
|
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the <A HREF = "thermo_style.html">thermo_style</A> command) with ID = <I>thermo_temp</I>
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and <I>thermo_press</I>. This means you can change the attributes of this
|
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fix's temperature or pressure via the
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<A HREF = "compute_modify.html">compute_modify</A> command or print this temperature
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or pressure during thermodynamic output via the <A HREF = "thermo_style.html">thermo_style
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custom</A> command using the appropriate compute-ID.
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It also means that changing attributes of <I>thermo_temp</I> or
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<I>thermo_press</I> will have no effect on this fix.
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</P>
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<HR>
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<P><B>Restart, fix_modify, output, run start/stop, minimize info:</B>
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</P>
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<P>This fix writes the values of E0, V0, and P0, as well as the
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state of all the thermostat and barostat
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variables to <A HREF = "restart.html">binary restart files</A>. See the
|
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<A HREF = "read_restart.html">read_restart</A> command for info on how to re-specify
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a fix in an input script that reads a restart file, so that the
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operation of the fix continues in an uninterrupted fashion.
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</P>
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<P>The <A HREF = "fix_modify.html">fix_modify</A> <I>e0</I>, <I>v0</I> and <I>p0</I> keywords
|
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can be used to define the values of these quantities. Note the
|
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the values for <I>e0</I> and <I>v0</I> are extensive, and so must correspond
|
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to the total energy and volume of the entire system, not energy and
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volume per atom. If any of these quantities are not specified, then the
|
||||
instanteous value in the system at the start of the simulation is used.
|
||||
</P>
|
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<P>The <A HREF = "fix_modify.html">fix_modify</A> <I>temp</I> and <I>press</I> options are
|
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supported by these fixes. You can use them to assign a
|
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<A HREF = "compute.html">compute</A> you have defined to this fix which will be used
|
||||
in its thermostatting or barostatting procedure, as described above.
|
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If you do this, note that the kinetic energy derived from the compute
|
||||
temperature should be consistent with the virial term computed using
|
||||
all atoms for the pressure. LAMMPS will warn you if you choose to
|
||||
compute temperature on a subset of atoms.
|
||||
</P>
|
||||
<P>The <A HREF = "fix_modify.html">fix_modify</A> <I>energy</I> option is supported by these
|
||||
fixes to add the energy change induced by Nose/Hoover thermostatting
|
||||
and barostatting to the system's potential energy as part of
|
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<A HREF = "thermo_style.html">thermodynamic output</A>. Either way, this energy is *not*
|
||||
included in the definition of internal energy E when calculating the value
|
||||
of Delta in the above equation.
|
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</P>
|
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<P>These fixes compute a global scalar and a global vector of quantities,
|
||||
which can be accessed by various <A HREF = "Section_howto.html#howto_15">output
|
||||
commands</A>. The scalar value calculated by
|
||||
these fixes is "extensive"; the vector values are "intensive".
|
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</P>
|
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<P>The scalar is the cumulative energy change due to the fix.
|
||||
</P>
|
||||
<P>The vector stores three quantities unique to this fix (Delta, Us, and up),
|
||||
followed by all the internal Nose/Hoover thermostat and barostat
|
||||
variables defined for <A HREF = "fix_nh.html">fix_style npt</A>. Delta is the deviation
|
||||
of the temperature from the target temperature, given by the above equation.
|
||||
Us and up are the shock and particle velocity correspponding to a steady
|
||||
shock calculated from the Rh conditions. They have units of distance/time.
|
||||
</P>
|
||||
<P><B>Restrictions:</B>
|
||||
</P>
|
||||
<P>This fix style is part of the SHOCK package. It is only enabled if
|
||||
LAMMPS was built with that package. See the <A HREF = "Section_start.html#start_3">Making
|
||||
LAMMPS</A> section for more info.
|
||||
</P>
|
||||
<P>All the usual restrictions for <A HREF = "fix_nh.html">fix_style npt</A> apply,
|
||||
plus the additional ones mentioned above.
|
||||
</P>
|
||||
<P><B>Related commands:</B>
|
||||
</P>
|
||||
<P><A HREF = "fix_msst.html">fix msst</A>, <A HREF = "fix_nh.html">fix npt</A>, <A HREF = "fix_modify.html">fix_modify</A>
|
||||
</P>
|
||||
<P><B>Default:</B>
|
||||
</P>
|
||||
<P>The keyword defaults are the same as those for <A HREF = "fix_nh.html">fix npt</A>
|
||||
</P>
|
||||
<HR>
|
||||
|
||||
<A NAME = "Ravelo"></A>
|
||||
|
||||
<P><B>(Ravelo)</B> Ravelo, Holian, Germann and Lomdahl, Phys Rev B, 70, 014103 (2004).
|
||||
</P>
|
||||
</HTML>
|
||||
211
doc/fix_nphug.txt
Normal file
211
doc/fix_nphug.txt
Normal file
@ -0,0 +1,211 @@
|
||||
"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
|
||||
|
||||
:link(lws,http://lammps.sandia.gov)
|
||||
:link(ld,Manual.html)
|
||||
:link(lc,Section_commands.html#comm)
|
||||
|
||||
:line
|
||||
|
||||
fix nphug command :h3
|
||||
|
||||
[Syntax:]
|
||||
|
||||
fix ID group-ID nphug keyword value ... :pre
|
||||
|
||||
ID, group-ID are documented in "fix"_fix.html command :ulb,l
|
||||
one or more keyword value pairs may be appended
|
||||
keyword = {temp} or {iso} or {aniso} or {tri} or {x} or {y} or {z} or {couple} or {tchain} or {pchain} or {mtk} or {tloop} or {ploop} or {nreset} or {drag} or {dilate} or {scaleyz} or {scalexz} or {scalexy}
|
||||
{temp} values = Value1 Value2 Tdamp
|
||||
Value1, Value2 = Nose-Hoover target temperatures, ignored by Hugoniostat
|
||||
Tdamp = temperature damping parameter (time units)
|
||||
{iso} or {aniso} or {tri} values = Pstart Pstop Pdamp
|
||||
Pstart,Pstop = scalar external pressures, must be equal (pressure units)
|
||||
Pdamp = pressure damping parameter (time units)
|
||||
{x} or {y} or {z} or {xy} or {yz} or {xz} values = Pstart Pstop Pdamp
|
||||
Pstart,Pstop = external stress tensor components, must be equal (pressure units)
|
||||
Pdamp = stress damping parameter (time units)
|
||||
{couple} = {none} or {xyz} or {xy} or {yz} or {xz}
|
||||
{tchain} value = length of thermostat chain (1 = single thermostat)
|
||||
{pchain} values = length of thermostat chain on barostat (0 = no thermostat)
|
||||
{mtk} value = {yes} or {no} = add in MTK adjustment term or not
|
||||
{tloop} value = number of sub-cycles to perform on thermostat
|
||||
{ploop} value = number of sub-cycles to perform on barostat thermostat
|
||||
{nreset} value = reset reference cell every this many timesteps
|
||||
{drag} value = drag factor added to barostat/thermostat (0.0 = no drag)
|
||||
{dilate} value = {all} or {partial}
|
||||
{scaleyz} value = {yes} or {no} = scale yz with lz
|
||||
{scalexz} value = {yes} or {no} = scale xz with lz
|
||||
{scalexy} value = {yes} or {no} = scale xy with ly :pre
|
||||
:ule
|
||||
|
||||
[Examples:]
|
||||
|
||||
fix myhug all nphug temp 1.0 1.0 10.0 z 40.0 40.0 70.0
|
||||
fix myhug all nphug temp 1.0 1.0 10.0 iso 40.0 40.0 70.0 drag 200.0 tchain 1 pchain 0
|
||||
|
||||
[Description:]
|
||||
|
||||
This command is a variant of the Nose-Hoover
|
||||
"fix npt"_fix_nh.html fix style.
|
||||
It performs time integration of the Hugoniostat equations
|
||||
of motion developed by Ravelo et al. "(Ravelo)"_#Ravelo.
|
||||
These equations compress the system to a state with average
|
||||
axial stress or pressure equal to the specified target value
|
||||
and that satisfies the Rankine-Hugoniot (RH)
|
||||
jump conditions for steady shocks.
|
||||
|
||||
The compression can be performed
|
||||
either
|
||||
hydrostatically (using keyword iso, aniso, or tri) or uniaxially
|
||||
(using keywords x, y, or z). In the hydrostatic case,
|
||||
the cell dimensions change dynamically so that the average axial stress
|
||||
in all three directions converges towards the specified target value.
|
||||
In the uniaxial case, the chosen cell dimension changes dynamically
|
||||
so that the average
|
||||
axial stress in that direction converges towards the target value. The
|
||||
other two cell dimensions are kept fixed (zero lateral strain).
|
||||
|
||||
This leads to the following additional restrictions on the keywords:
|
||||
|
||||
One and only one of the following keywords should be used: iso, aniso, tri, x, y, z,
|
||||
|
||||
The specified initial and final target pressures must be the same.
|
||||
|
||||
The keywords xy, xz, yz may not be used.
|
||||
|
||||
The only admissible value for the couple keyword is xyz,
|
||||
which has the same effect as keyword iso
|
||||
|
||||
The temp keyword must be used in order to specify the time constant for
|
||||
kinetic energy relaxation, but initial and final target temperature values
|
||||
are ignored. :ul
|
||||
|
||||
Essentially, a Hugoniostat simulation is an NPT simulation in which the
|
||||
user-specified target temperature is replaced with a time-dependent
|
||||
target temperature Tt obtained from the following equation:
|
||||
|
||||
Tt - T = (0.5*(P+P0)(V0-V)+E0-E)/(Ndof kB) = Delta
|
||||
|
||||
where T and Tt are the instantaneous and target temperatures,
|
||||
P and P0 are the instantaneous and reference pressure or axial stress,
|
||||
depending on whether hydrostatic or uniaxial compression is being
|
||||
performed, V and V0 are the instantaneous and reference volumes,
|
||||
E and E0 are the instantaneous and reference internal energy (potential
|
||||
plus kinetic), Ndof is the number of degrees of freedom used in the
|
||||
definition of temperature, and kB is the Boltzmann constant. Delta is the
|
||||
negative deviation of the instantaneous temperature from the target temperature.
|
||||
The values of E0, V0, and P0 are the instantaneous values at the start of
|
||||
the simulation. These can be overridden using the fix_modify keywords {e0},
|
||||
{v0}, and {p0} described below.
|
||||
|
||||
:line
|
||||
|
||||
IMPORTANT NOTE: Unlike the "fix
|
||||
temp/berendsen"_fix_temp_berendsen.html command which performs
|
||||
thermostatting but NO time integration, this fix performs
|
||||
thermostatting/barostatting AND time integration. Thus you should not
|
||||
use any other time integration fix, such as "fix nve"_fix_nve.html on
|
||||
atoms to which this fix is applied. Likewise, this fix should not be
|
||||
used on atoms that have their temperature controlled by another fix
|
||||
- e.g. by "fix langevin"_fix_nh.html or "fix temp/rescale"_fix_temp_rescale.html
|
||||
commands.
|
||||
|
||||
:line
|
||||
|
||||
This fix compute a temperature and pressure each timestep. To do
|
||||
this, the fix creates its own computes of style "temp" and "pressure",
|
||||
as if one of these two sets of commands had been issued:
|
||||
|
||||
compute fix-ID_temp group-ID temp
|
||||
compute fix-ID_press group-ID pressure fix-ID_temp :pre
|
||||
|
||||
compute fix-ID_temp all temp
|
||||
compute fix-ID_press all pressure fix-ID_temp :pre
|
||||
|
||||
See the "compute temp"_compute_temp.html and "compute
|
||||
pressure"_compute_pressure.html commands for details. Note that the
|
||||
IDs of the new computes are the fix-ID + underscore + "temp" or fix_ID
|
||||
+ underscore + "press". For fix nvt, the group for the new computes
|
||||
is the same as the fix group. For fix nph and fix npt, the group for
|
||||
the new computes is "all" since pressure is computed for the entire
|
||||
system.
|
||||
|
||||
Note that these are NOT the computes used by thermodynamic output (see
|
||||
the "thermo_style"_thermo_style.html command) with ID = {thermo_temp}
|
||||
and {thermo_press}. This means you can change the attributes of this
|
||||
fix's temperature or pressure via the
|
||||
"compute_modify"_compute_modify.html command or print this temperature
|
||||
or pressure during thermodynamic output via the "thermo_style
|
||||
custom"_thermo_style.html command using the appropriate compute-ID.
|
||||
It also means that changing attributes of {thermo_temp} or
|
||||
{thermo_press} will have no effect on this fix.
|
||||
|
||||
:line
|
||||
|
||||
[Restart, fix_modify, output, run start/stop, minimize info:]
|
||||
|
||||
This fix writes the values of E0, V0, and P0, as well as the
|
||||
state of all the thermostat and barostat
|
||||
variables to "binary restart files"_restart.html. See the
|
||||
"read_restart"_read_restart.html command for info on how to re-specify
|
||||
a fix in an input script that reads a restart file, so that the
|
||||
operation of the fix continues in an uninterrupted fashion.
|
||||
|
||||
The "fix_modify"_fix_modify.html {e0}, {v0} and {p0} keywords
|
||||
can be used to define the values of these quantities. Note the
|
||||
the values for {e0} and {v0} are extensive, and so must correspond
|
||||
to the total energy and volume of the entire system, not energy and
|
||||
volume per atom. If any of these quantities are not specified, then the
|
||||
instanteous value in the system at the start of the simulation is used.
|
||||
|
||||
The "fix_modify"_fix_modify.html {temp} and {press} options are
|
||||
supported by these fixes. You can use them to assign a
|
||||
"compute"_compute.html you have defined to this fix which will be used
|
||||
in its thermostatting or barostatting procedure, as described above.
|
||||
If you do this, note that the kinetic energy derived from the compute
|
||||
temperature should be consistent with the virial term computed using
|
||||
all atoms for the pressure. LAMMPS will warn you if you choose to
|
||||
compute temperature on a subset of atoms.
|
||||
|
||||
The "fix_modify"_fix_modify.html {energy} option is supported by these
|
||||
fixes to add the energy change induced by Nose/Hoover thermostatting
|
||||
and barostatting to the system's potential energy as part of
|
||||
"thermodynamic output"_thermo_style.html. Either way, this energy is *not*
|
||||
included in the definition of internal energy E when calculating the value
|
||||
of Delta in the above equation.
|
||||
|
||||
These fixes compute a global scalar and a global vector of quantities,
|
||||
which can be accessed by various "output
|
||||
commands"_Section_howto.html#howto_15. The scalar value calculated by
|
||||
these fixes is "extensive"; the vector values are "intensive".
|
||||
|
||||
The scalar is the cumulative energy change due to the fix.
|
||||
|
||||
The vector stores three quantities unique to this fix (Delta, Us, and up),
|
||||
followed by all the internal Nose/Hoover thermostat and barostat
|
||||
variables defined for "fix_style npt"_fix_nh.html. Delta is the deviation
|
||||
of the temperature from the target temperature, given by the above equation.
|
||||
Us and up are the shock and particle velocity correspponding to a steady
|
||||
shock calculated from the Rh conditions. They have units of distance/time.
|
||||
|
||||
[Restrictions:]
|
||||
|
||||
This fix style is part of the SHOCK package. It is only enabled if
|
||||
LAMMPS was built with that package. See the "Making
|
||||
LAMMPS"_Section_start.html#start_3 section for more info.
|
||||
|
||||
All the usual restrictions for "fix_style npt"_fix_nh.html apply,
|
||||
plus the additional ones mentioned above.
|
||||
|
||||
[Related commands:]
|
||||
|
||||
"fix msst"_fix_msst.html, "fix npt"_fix_nh.html, "fix_modify"_fix_modify.html
|
||||
|
||||
[Default:]
|
||||
|
||||
The keyword defaults are the same as those for "fix npt"_fix_nh.html
|
||||
|
||||
:line
|
||||
|
||||
:link(Ravelo)
|
||||
[(Ravelo)] Ravelo, Holian, Germann and Lomdahl, Phys Rev B, 70, 014103 (2004).
|
||||
Reference in New Issue
Block a user