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sjplimp 2007-06-20 13:09:50 +00:00
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14
doc/Section_commands.html
View File

@ -317,13 +317,13 @@ descriptions of each style or click on the style itself for a full
description:
</P>
<DIV ALIGN=center><TABLE WIDTH="0%" BORDER=1 >
<TR ALIGN="center"><TD ><A HREF = "fix_addforce.html">addforce</A></TD><TD ><A HREF = "fix_aveforce.html">aveforce</A></TD><TD ><A HREF = "fix_ave_spatial.html">ave/spatial</A></TD><TD ><A HREF = "fix_ave_time.html">ave/time</A></TD><TD ><A HREF = "fix_box_relax.html">box/relax</A></TD><TD ><A HREF = "fix_com.html">com</A></TD><TD ><A HREF = "fix_deform.html">deform</A></TD><TD ><A HREF = "fix_deposit.html">deposit</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "fix_drag.html">drag</A></TD><TD ><A HREF = "fix_efield.html">efield</A></TD><TD ><A HREF = "fix_enforce2d.html">enforce2d</A></TD><TD ><A HREF = "fix_freeze.html">freeze</A></TD><TD ><A HREF = "fix_gran_diag.html">gran/diag</A></TD><TD ><A HREF = "fix_gravity.html">gravity</A></TD><TD ><A HREF = "fix_gyration.html">gyration</A></TD><TD ><A HREF = "fix_heat.html">heat</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "fix_indent.html">indent</A></TD><TD ><A HREF = "fix_langevin.html">langevin</A></TD><TD ><A HREF = "fix_lineforce.html">lineforce</A></TD><TD ><A HREF = "fix_msd.html">msd</A></TD><TD ><A HREF = "fix_momentum.html">momentum</A></TD><TD ><A HREF = "fix_nph.html">nph</A></TD><TD ><A HREF = "fix_npt.html">npt</A></TD><TD ><A HREF = "fix_npt_asphere.html">npt/asphere</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "fix_nve.html">nve</A></TD><TD ><A HREF = "fix_nve_asphere.html">nve/asphere</A></TD><TD ><A HREF = "fix_nve_dipole.html">nve/dipole</A></TD><TD ><A HREF = "fix_nve_gran.html">nve/gran</A></TD><TD ><A HREF = "fix_nve_noforce.html">nve/noforce</A></TD><TD ><A HREF = "fix_nvt.html">nvt</A></TD><TD ><A HREF = "fix_nvt_sllod.html">nvt/sllod</A></TD><TD ><A HREF = "fix_nvt_asphere.html">nvt/asphere</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "fix_orient_fcc.html">orient/fcc</A></TD><TD ><A HREF = "fix_planeforce.html">planeforce</A></TD><TD ><A HREF = "fix_poems.html">poems</A></TD><TD ><A HREF = "fix_pour.html">pour</A></TD><TD ><A HREF = "fix_print.html">print</A></TD><TD ><A HREF = "fix_rdf.html">rdf</A></TD><TD ><A HREF = "fix_recenter.html">recenter</A></TD><TD ><A HREF = "fix_rigid.html">rigid</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "fix_setforce.html">setforce</A></TD><TD ><A HREF = "fix_shake.html">shake</A></TD><TD ><A HREF = "fix_spring.html">spring</A></TD><TD ><A HREF = "fix_spring_rg.html">spring/rg</A></TD><TD ><A HREF = "fix_spring_self.html">spring/self</A></TD><TD ><A HREF = "fix_temp_rescale.html">temp/rescale</A></TD><TD ><A HREF = "fix_tmd.html">tmd</A></TD><TD ><A HREF = "fix_viscous.html">viscous</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "fix_wall_gran.html">wall/gran</A></TD><TD ><A HREF = "fix_wall_lj93.html">wall/lj93</A></TD><TD ><A HREF = "fix_wall_lj126.html">wall/lj126</A></TD><TD ><A HREF = "fix_wall_reflect.html">wall/reflect</A></TD><TD ><A HREF = "fix_wiggle.html">wiggle</A>
<TR ALIGN="center"><TD ><A HREF = "fix_addforce.html">addforce</A></TD><TD ><A HREF = "fix_aveforce.html">aveforce</A></TD><TD ><A HREF = "fix_ave_spatial.html">ave/spatial</A></TD><TD ><A HREF = "fix_ave_time.html">ave/time</A></TD><TD ><A HREF = "fix_com.html">com</A></TD><TD ><A HREF = "fix_deform.html">deform</A></TD><TD ><A HREF = "fix_deposit.html">deposit</A></TD><TD ><A HREF = "fix_drag.html">drag</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "fix_efield.html">efield</A></TD><TD ><A HREF = "fix_enforce2d.html">enforce2d</A></TD><TD ><A HREF = "fix_freeze.html">freeze</A></TD><TD ><A HREF = "fix_gran_diag.html">gran/diag</A></TD><TD ><A HREF = "fix_gravity.html">gravity</A></TD><TD ><A HREF = "fix_gyration.html">gyration</A></TD><TD ><A HREF = "fix_heat.html">heat</A></TD><TD ><A HREF = "fix_indent.html">indent</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "fix_langevin.html">langevin</A></TD><TD ><A HREF = "fix_lineforce.html">lineforce</A></TD><TD ><A HREF = "fix_msd.html">msd</A></TD><TD ><A HREF = "fix_momentum.html">momentum</A></TD><TD ><A HREF = "fix_nph.html">nph</A></TD><TD ><A HREF = "fix_npt.html">npt</A></TD><TD ><A HREF = "fix_npt_asphere.html">npt/asphere</A></TD><TD ><A HREF = "fix_nve.html">nve</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "fix_nve_asphere.html">nve/asphere</A></TD><TD ><A HREF = "fix_nve_dipole.html">nve/dipole</A></TD><TD ><A HREF = "fix_nve_gran.html">nve/gran</A></TD><TD ><A HREF = "fix_nve_noforce.html">nve/noforce</A></TD><TD ><A HREF = "fix_nvt.html">nvt</A></TD><TD ><A HREF = "fix_nvt_asphere.html">nvt/asphere</A></TD><TD ><A HREF = "fix_nvt_sllod.html">nvt/sllod</A></TD><TD ><A HREF = "fix_orient_fcc.html">orient/fcc</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "fix_planeforce.html">planeforce</A></TD><TD ><A HREF = "fix_poems.html">poems</A></TD><TD ><A HREF = "fix_pour.html">pour</A></TD><TD ><A HREF = "fix_print.html">print</A></TD><TD ><A HREF = "fix_rdf.html">rdf</A></TD><TD ><A HREF = "fix_recenter.html">recenter</A></TD><TD ><A HREF = "fix_rigid.html">rigid</A></TD><TD ><A HREF = "fix_setforce.html">setforce</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "fix_shake.html">shake</A></TD><TD ><A HREF = "fix_spring.html">spring</A></TD><TD ><A HREF = "fix_spring_rg.html">spring/rg</A></TD><TD ><A HREF = "fix_spring_self.html">spring/self</A></TD><TD ><A HREF = "fix_temp_rescale.html">temp/rescale</A></TD><TD ><A HREF = "fix_tmd.html">tmd</A></TD><TD ><A HREF = "fix_viscous.html">viscous</A></TD><TD ><A HREF = "fix_wall_gran.html">wall/gran</A></TD></TR>
<TR ALIGN="center"><TD ><A HREF = "fix_wall_lj126.html">wall/lj126</A></TD><TD ><A HREF = "fix_wall_lj93.html">wall/lj93</A></TD><TD ><A HREF = "fix_wall_reflect.html">wall/reflect</A></TD><TD ><A HREF = "fix_wiggle.html">wiggle</A>
</TD></TR></TABLE></DIV>
<HR>

5
doc/Section_commands.txt
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@ -377,7 +377,6 @@ description:
"aveforce"_fix_aveforce.html,
"ave/spatial"_fix_ave_spatial.html,
"ave/time"_fix_ave_time.html,
"box/relax"_fix_box_relax.html,
"com"_fix_com.html,
"deform"_fix_deform.html,
"deposit"_fix_deposit.html,
@ -403,8 +402,8 @@ description:
"nve/gran"_fix_nve_gran.html,
"nve/noforce"_fix_nve_noforce.html,
"nvt"_fix_nvt.html,
"nvt/sllod"_fix_nvt_sllod.html,
"nvt/asphere"_fix_nvt_asphere.html,
"nvt/sllod"_fix_nvt_sllod.html,
"orient/fcc"_fix_orient_fcc.html,
"planeforce"_fix_planeforce.html,
"poems"_fix_poems.html,
@ -422,8 +421,8 @@ description:
"tmd"_fix_tmd.html,
"viscous"_fix_viscous.html,
"wall/gran"_fix_wall_gran.html,
"wall/lj93"_fix_wall_lj93.html,
"wall/lj126"_fix_wall_lj126.html,
"wall/lj93"_fix_wall_lj93.html,
"wall/reflect"_fix_wall_reflect.html,
"wiggle"_fix_wiggle.html :tb(c=8,ea=c)

6
doc/compute.html
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@ -75,6 +75,7 @@ and what it does. Here is an alphabetic list of compute styles
defined in LAMMPS:
</P>
<UL><LI><A HREF = "compute_centro_atom.html">centro/atom</A> - centro-symmetry parameter for each atom
<LI><A HREF = "compute_coord_atom.html">coord/atom</A> - coordination number for each atom
<LI><A HREF = "compute_epair_atom.html">epair/atom</A> - pairwise energy for each atom
<LI><A HREF = "compute_etotal_atom.html">etotal/atom</A> - total energy (ke + epair) for each atom
<LI><A HREF = "compute_ke_atom.html">ke/atom</A> - kinetic energy for each atom
@ -83,8 +84,11 @@ defined in LAMMPS:
<LI><A HREF = "compute_rotate_gran.html">rotate/gran</A> - rotational energy of granular atoms
<LI><A HREF = "compute_stress_atom.html">stress/atom</A> - stress tensor for each atom
<LI><A HREF = "compute_temp.html">temp</A> - temperature of group of atoms
<LI><A HREF = "compute_temp_asphere.html">temp/asphere</A> - temperature of aspherical particles
<LI><A HREF = "compute_temp_deform.html">temp/deform</A> - temperature excluding box deformation velocity
<LI><A HREF = "compute_temp_dipole.html">temp/dipole</A> - temperature of point dipolar particles
<LI><A HREF = "compute_temp_partial.html">temp/partial</A> - temperature excluding one or more dimensions of velocity
<LI><A HREF = "compute_temp_ramp.html">temp/ramp</A> - temperature after subtracting a ramped velocity component
<LI><A HREF = "compute_temp_ramp.html">temp/ramp</A> - temperature excluding ramped velocity component
<LI><A HREF = "compute_temp_region.html">temp/region</A> - temperature of a region of atoms
<LI><A HREF = "compute_variable.html">variable</A> - calculate a scalar value from a variable
<LI><A HREF = "compute_variable_atom.html">variable/atom</A> - calculate a formula for each atom

6
doc/compute.txt
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@ -72,6 +72,7 @@ and what it does. Here is an alphabetic list of compute styles
defined in LAMMPS:
"centro/atom"_compute_centro_atom.html - centro-symmetry parameter for each atom
"coord/atom"_compute_coord_atom.html - coordination number for each atom
"epair/atom"_compute_epair_atom.html - pairwise energy for each atom
"etotal/atom"_compute_etotal_atom.html - total energy (ke + epair) for each atom
"ke/atom"_compute_ke_atom.html - kinetic energy for each atom
@ -80,8 +81,11 @@ defined in LAMMPS:
"rotate/gran"_compute_rotate_gran.html - rotational energy of granular atoms
"stress/atom"_compute_stress_atom.html - stress tensor for each atom
"temp"_compute_temp.html - temperature of group of atoms
"temp/asphere"_compute_temp_asphere.html - temperature of aspherical particles
"temp/deform"_compute_temp_deform.html - temperature excluding box deformation velocity
"temp/dipole"_compute_temp_dipole.html - temperature of point dipolar particles
"temp/partial"_compute_temp_partial.html - temperature excluding one or more dimensions of velocity
"temp/ramp"_compute_temp_ramp.html - temperature after subtracting a ramped velocity component
"temp/ramp"_compute_temp_ramp.html - temperature excluding ramped velocity component
"temp/region"_compute_temp_region.html - temperature of a region of atoms
"variable"_compute_variable.html - calculate a scalar value from a variable
"variable/atom"_compute_variable_atom.html - calculate a formula for each atom :ul

1
doc/fix.html
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@ -67,7 +67,6 @@ made to the old fix via the <A HREF = "fix_modify.html">fix_modify</A> command.
<LI><A HREF = "fix_aveforce.html">fix aveforce</A> - add an averaged force to each atom
<LI><A HREF = "fix_ave_spatial.html">fix ave/spatial</A> - output per-atom quantities by layer
<LI><A HREF = "fix_ave_time.html">fix ave/time</A> - output time-averaged compute quantities
<LI><A HREF = "fix_box_relax.html">fix box/relax</A> - relax box size during a minimization
<LI><A HREF = "fix_com.html">fix com</A> - compute a center-of-mass
<LI><A HREF = "fix_desosit.html">fix deposit</A> - add new atoms above a surface
<LI><A HREF = "fix_drag.html">fix drag</A> - drag atoms towards a defined coordinate

1
doc/fix.txt
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@ -64,7 +64,6 @@ Here is an alphabetic list of fix styles defined in LAMMPS:
"fix aveforce"_fix_aveforce.html - add an averaged force to each atom
"fix ave/spatial"_fix_ave_spatial.html - output per-atom quantities by layer
"fix ave/time"_fix_ave_time.html - output time-averaged compute quantities
"fix box/relax"_fix_box_relax.html - relax box size during a minimization
"fix com"_fix_com.html - compute a center-of-mass
"fix deposit"_fix_desosit.html - add new atoms above a surface
"fix drag"_fix_drag.html - drag atoms towards a defined coordinate

128
doc/fix_uniaxial.html
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@ -1,128 +0,0 @@
<HTML>
<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>
</CENTER>
<HR>
<H3>fix uniaxial command
</H3>
<P><B>Syntax:</B>
</P>
<PRE>fix ID group-ID uniaxial N keyword dim amount
</PRE>
<UL><LI>ID, group-ID are documented in <A HREF = "fix.html">fix</A> command
<LI>uniaxial = style name of this fix command
<LI>N = perform uniaxial rescaling every this many timesteps
<LI>dim = <I>x</I> or <I>y</I> or <I>z</I>
<LI>strain = uniaxial strain in dim (2.0 = 2x larger)
</UL>
<P><B>Examples:</B>
</P>
<PRE>fix 1 all uniaxial 100 x 2.0
</PRE>
<P><B>Description:</B>
</P>
<P>Enable a uniaxial dilation/contraction of the simulation box during a
simulation. For example if the direction is X and the strain is 2,
then the final box size is 2L, L/sqrt(2), L/sqrt(2), where L**3 is a
cube with the same volume as the initial box, which need not be cubic.
</P>
<P>The chosen direction is ramped linearly during the course of the run
to its final value. The <A HREF = "run.html">run</A> command documents how to make
the ramping take place across multiple runs.
</P>
<P>If the two perpendicular box sizes are equal then the deformation
pathway is uniaxial at each timestep. If the two perpendicular box
length sizes differ, then their aspect ratio will be linearily ramped
down to 1. Irregardless of the initial box shape the total volume is
constant during the deformation. Additional details provided by
Carsten Svaneborg (Max Planck Institute for Complex Systems, Dresden,
Germany) who authored this fix, are at the bottom of this page.
</P>
<P>The initial simulation box boundaries at the beginning of a run are
specified by the <A HREF = "create_box.html">create_box</A> or
<A HREF = "read_data.html">read_data</A> or <A HREF = "read_restart.html">read_restart</A> command
used to setup the simulation, or they are the values at the end of the
previous run. Every Nth timestep during the run, the various
dimensions are expanded or contracted. The coordinates of all atoms
in the group are also scaled to the new box size.
</P>
<P><B>Restrictions:</B>
</P>
<P>To use this fix, all dimensions of the system must be periodic.
</P>
<P><B>Related commands:</B> none
</P>
<P><B>Default:</B> none
</P>
<P><B>Extra Notes:</B>
</P>
<P>The uniaxial deformation is performed as follows:
</P>
<P>For notational simplicity the deformation is assumed to be in
the X direction with final strain lambda. alpha denotes an
arbitrary Cartesian direction.
</P>
<P>The initial strain is obtained from box dimensions:
</P>
<PRE>lambdai_alpha = Box(alpha)/power(Box(0)*Box(1)*Box(2),1/3)
</PRE>
<P>The final strain lambda in dir is specified:
</P>
<PRE>lambdaf_x = lambda
lambda_y = lambda_z = 1/sqrt(lambda)
</PRE>
<P>Volume conservation implies lambda_x(t)*lambda_y(t)lambda_z(t) = 1.0
for all times. Rather than time, let delta is denotes reduced time in
the interval from 0 to 1.
</P>
<P>We want a linear ramp in the specified strain component, such that MD
time steps and uniaxial strain are linearly related:
</P>
<PRE>lambda_x(delta) = lambdai_x (1-delta) + lambdaf_x
</PRE>
<P>The problem that remains is to choose a deformation pathway for
lambda_y(delta) and lambda_z(delta) that agrees with the initial and
final strains, and at all times conserves volume. Secondly the pathway
should be symmetric if the box has y<->z symmetry.
</P>
<P>In the case where the initial box is symmetric in yz, this follows
from volume conservation:
</P>
<PRE>lambda_y(d) = lambda_z(d) = 1/sqrt(lambda_x(d))
</PRE>
<P>However, in general the initial box dimensions in the y and z directions
need not be the same so assume a relation:
</P>
<PRE>lambda_y(d) = alpha(d)lambda_z(d)
</PRE>
<P>From volume conservation it follows that
</P>
<PRE>lambda_y(d) = sqrt(alpha(d)/lambda_x(d))
lambda_z(d) = 1/sqrt(alpha(d)*lambda_x(d))
</PRE>
<P>The asymmetry parameter has to fulfill the following boundary
conditions:
</P>
<PRE>initial alpha(d=0) = lambdai_y/lambdai_z
final alpha(d=1) = 1
</PRE>
<P>Any interpolation that does this will by define a continuous volume
conserving deformation from the initial to the desired final state.
The freedom of choice here is e.g. to relax the asymetry of the box
very fast, and then slowly elongate along x, or to do this more
slowly.
</P>
<P>The choice used in the code is:
</P>
<PRE>alpha(d) = lambdai_y/lambdai_z (1-d) + d
</PRE>
<P>Note in some cases like strain <1 2 0.5> -> strain <2 0.707107
0.707107> the perpendicular strains do not follow a monotonic curve.
</P>
</HTML>

123
doc/fix_uniaxial.txt
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@ -1,123 +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,Section_commands.html#comm)
:line
fix uniaxial command :h3
[Syntax:]
fix ID group-ID uniaxial N keyword dim amount :pre
ID, group-ID are documented in "fix"_fix.html command
uniaxial = style name of this fix command
N = perform uniaxial rescaling every this many timesteps
dim = {x} or {y} or {z}
strain = uniaxial strain in dim (2.0 = 2x larger) :ul
[Examples:]
fix 1 all uniaxial 100 x 2.0 :pre
[Description:]
Enable a uniaxial dilation/contraction of the simulation box during a
simulation. For example if the direction is X and the strain is 2,
then the final box size is 2L, L/sqrt(2), L/sqrt(2), where L**3 is a
cube with the same volume as the initial box, which need not be cubic.
The chosen direction is ramped linearly during the course of the run
to its final value. The "run"_run.html command documents how to make
the ramping take place across multiple runs.
If the two perpendicular box sizes are equal then the deformation
pathway is uniaxial at each timestep. If the two perpendicular box
length sizes differ, then their aspect ratio will be linearily ramped
down to 1. Irregardless of the initial box shape the total volume is
constant during the deformation. Additional details provided by
Carsten Svaneborg (Max Planck Institute for Complex Systems, Dresden,
Germany) who authored this fix, are at the bottom of this page.
The initial simulation box boundaries at the beginning of a run are
specified by the "create_box"_create_box.html or
"read_data"_read_data.html or "read_restart"_read_restart.html command
used to setup the simulation, or they are the values at the end of the
previous run. Every Nth timestep during the run, the various
dimensions are expanded or contracted. The coordinates of all atoms
in the group are also scaled to the new box size.
[Restrictions:]
To use this fix, all dimensions of the system must be periodic.
[Related commands:] none
[Default:] none
[Extra Notes:]
The uniaxial deformation is performed as follows:
For notational simplicity the deformation is assumed to be in
the X direction with final strain lambda. alpha denotes an
arbitrary Cartesian direction.
The initial strain is obtained from box dimensions:
lambdai_alpha = Box(alpha)/power(Box(0)*Box(1)*Box(2),1/3) :pre
The final strain lambda in dir is specified:
lambdaf_x = lambda
lambda_y = lambda_z = 1/sqrt(lambda) :pre
Volume conservation implies lambda_x(t)*lambda_y(t)lambda_z(t) = 1.0
for all times. Rather than time, let delta is denotes reduced time in
the interval from 0 to 1.
We want a linear ramp in the specified strain component, such that MD
time steps and uniaxial strain are linearly related:
lambda_x(delta) = lambdai_x (1-delta) + lambdaf_x :pre
The problem that remains is to choose a deformation pathway for
lambda_y(delta) and lambda_z(delta) that agrees with the initial and
final strains, and at all times conserves volume. Secondly the pathway
should be symmetric if the box has y<->z symmetry.
In the case where the initial box is symmetric in yz, this follows
from volume conservation:
lambda_y(d) = lambda_z(d) = 1/sqrt(lambda_x(d)) :pre
However, in general the initial box dimensions in the y and z directions
need not be the same so assume a relation:
lambda_y(d) = alpha(d)lambda_z(d) :pre
From volume conservation it follows that
lambda_y(d) = sqrt(alpha(d)/lambda_x(d))
lambda_z(d) = 1/sqrt(alpha(d)*lambda_x(d)) :pre
The asymmetry parameter has to fulfill the following boundary
conditions:
initial alpha(d=0) = lambdai_y/lambdai_z
final alpha(d=1) = 1 :pre
Any interpolation that does this will by define a continuous volume
conserving deformation from the initial to the desired final state.
The freedom of choice here is e.g. to relax the asymetry of the box
very fast, and then slowly elongate along x, or to do this more
slowly.
The choice used in the code is:
alpha(d) = lambdai_y/lambdai_z (1-d) + d :pre
Note in some cases like strain <1 2 0.5> -> strain <2 0.707107
0.707107> the perpendicular strains do not follow a monotonic curve.

69
doc/fix_volume_rescale.html
View File

@ -1,69 +0,0 @@
<HTML>
<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>
</CENTER>
<HR>
<H3>fix volume/rescale command
</H3>
<P><B>Syntax:</B>
</P>
<PRE>fix ID group-ID volume/rescale N keyword args ...
</PRE>
<UL><LI>ID, group-ID are documented in <A HREF = "fix.html">fix</A> command
</UL>
<LI>volume/rescale = style name of this fix command
<LI>N = perform volume rescaling every this many timesteps
<LI>one or more keyword/value pairs may be appended to the args
<LI>keyword = <I>x</I> or <I>y</I> or <I>z</I>
<PRE> <I>x</I>, <I>y</I>, <I>z</I> args = lo,hi = desired simulation box boundaries
at end of run (distance units)
</PRE>
</UL>
<P><B>Examples:</B>
</P>
<PRE>fix 1 all volume/rescale 100 x -9.0 9.0 z -5.0 5.0
</PRE>
<P><B>Description:</B>
</P>
<P>Enable a volume (density) change during a simulation. Each of the 3
box dimensions is controlled separately. Any dimension being varied
by this command must be periodic - see the <A HREF = "boundary.html">boundary</A>
command. Dimensions not varied by this command can be periodic or
non-periodic. The volume associated with an unspecified dimension can
also be controlled by a <A HREF = "fix_npt.html">fix npt</A> or <A HREF = "fix_nph.html">fix
nph</A> command.
</P>
<P>The initial simulation box boundaries at the beginning of a run are
specified by the <A HREF = "create_box.html">create_box</A> or
<A HREF = "read_data.html">read_data</A> or <A HREF = "read_restart.html">read_restart</A> command
used to setup the simulation, or they are the values at the end of the
previous run. The desired simulation box boundaries at the end of the
run are given by the <I>lo</I> and <I>hi</I> arguments. See the
<A HREF = "units.html">units</A> command for a discussion of distance units.
</P>
<P>Every Nth timestep during the run, the simulation box is expanded or
contracted to a ramped value between the initial and final values.
The <A HREF = "run.html">run</A> command documents how to make the ramping take
place across multiple runs. The coordinates of all atoms in the group
are also scaled to the new box size.
</P>
<P><B>Restrictions:</B>
</P>
<P>Any dimension being varied by this fix must be periodic.
</P>
<P><B>Related commands:</B> none
</P>
<P><B>Default:</B> none
</P>
</HTML>

58
doc/fix_volume_rescale.txt
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@ -1,58 +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,Section_commands.html#comm)
:line
fix volume/rescale command :h3
[Syntax:]
fix ID group-ID volume/rescale N keyword args ... :pre
ID, group-ID are documented in "fix"_fix.html command :ul
volume/rescale = style name of this fix command :l
N = perform volume rescaling every this many timesteps :l
one or more keyword/value pairs may be appended to the args :l
keyword = {x} or {y} or {z} :l
{x}, {y}, {z} args = lo,hi = desired simulation box boundaries
at end of run (distance units) :pre
:ule
[Examples:]
fix 1 all volume/rescale 100 x -9.0 9.0 z -5.0 5.0 :pre
[Description:]
Enable a volume (density) change during a simulation. Each of the 3
box dimensions is controlled separately. Any dimension being varied
by this command must be periodic - see the "boundary"_boundary.html
command. Dimensions not varied by this command can be periodic or
non-periodic. The volume associated with an unspecified dimension can
also be controlled by a "fix npt"_fix_npt.html or "fix
nph"_fix_nph.html command.
The initial simulation box boundaries at the beginning of a run are
specified by the "create_box"_create_box.html or
"read_data"_read_data.html or "read_restart"_read_restart.html command
used to setup the simulation, or they are the values at the end of the
previous run. The desired simulation box boundaries at the end of the
run are given by the {lo} and {hi} arguments. See the
"units"_units.html command for a discussion of distance units.
Every Nth timestep during the run, the simulation box is expanded or
contracted to a ramped value between the initial and final values.
The "run"_run.html command documents how to make the ramping take
place across multiple runs. The coordinates of all atoms in the group
are also scaled to the new box size.
[Restrictions:]
Any dimension being varied by this fix must be periodic.
[Related commands:] none
[Default:] none