git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@1471 f3b2605a-c512-4ea7-a41b-209d697bcdaa

This commit is contained in:
sjplimp 2008-02-08 20:00:41 +00:00
parent a15113ed1f
commit 37bfe6ac0e
2 changed files with 28 additions and 4 deletions

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@ -27,7 +27,7 @@
<LI>zero or more keyword/value pairs may be appended
<PRE>keyword = <I>axes</I> or <I>scale</I> or <I>region</I>
<PRE>keyword = <I>axes</I> or <I>scale</I> or <I>region</I> or <I>weight</I>
<I>axes</I> values = xflag yflag zflag
xflag,yflag,zflag = 0/1 to exclude/include a dimension in the thermostat
<I>scale</I> values = type ratio
@ -36,6 +36,8 @@
<I>region</I> values = region-ID
region-ID = ID of region to apply thermostat to
</PRE>
<I>weight</I> values = factor
factor = scale factor to apply to random thermal force
</UL>
<P><B>Examples:</B>
@ -112,6 +114,13 @@ values.
specified geometric region (and in the fix group). Since atoms can
enter/leave a region, this test is performed each timestep.
</P>
<P>The keyword <I>weight</I> applies the specified scale factor to the Fr term
in the above equation. A value of 1.0 (the default) leaves it
unchanged. A value smaller/greater than 1.0 scales its relative
magnitude as compared to the Ff term. This can be useful for some
models of thermostatting where a different coupling to the background
solvent (coupling constant) is desired.
</P>
<P>As noted above, fix <I>langevin</I> does not update the coordinates or
velocities of its atoms, only the forces. It is normally used with a
<A HREF = "fix_nve.html">fix nve</A> that does the time integration. Fix <I>langevin</I>
@ -146,7 +155,10 @@ commands</A>.
<P><A HREF = "fix_nvt.html">fix nvt</A>, <A HREF = "fix_temp_rescale.html">fix temp/rescale</A>, <A HREF = "fix_viscous.html">fix
viscous</A>
</P>
<P><B>Default:</B> none
<P><B>Default:</B>
</P>
<P>The option defaults are axes = 1 1 1, scale = 1.0 for all types, no
region, and weight = 1.0.
</P>
<A NAME = "Dunweg"></A>

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@ -18,7 +18,7 @@ Tstart,Tstop = desired temperature at start/end of run (temperature units) :l
damp = damping parameter (time units) :l
seed = random # seed to use for white noise (positive integer) :l
zero or more keyword/value pairs may be appended :l
keyword = {axes} or {scale} or {region}
keyword = {axes} or {scale} or {region} or {weight}
{axes} values = xflag yflag zflag
xflag,yflag,zflag = 0/1 to exclude/include a dimension in the thermostat
{scale} values = type ratio
@ -26,6 +26,8 @@ keyword = {axes} or {scale} or {region}
ratio = factor to scale the damping coefficient by
{region} values = region-ID
region-ID = ID of region to apply thermostat to :pre
{weight} values = factor
factor = scale factor to apply to random thermal force
:ule
[Examples:]
@ -102,6 +104,13 @@ The keyword {region} applies the fix only to atoms that are in the
specified geometric region (and in the fix group). Since atoms can
enter/leave a region, this test is performed each timestep.
The keyword {weight} applies the specified scale factor to the Fr term
in the above equation. A value of 1.0 (the default) leaves it
unchanged. A value smaller/greater than 1.0 scales its relative
magnitude as compared to the Ff term. This can be useful for some
models of thermostatting where a different coupling to the background
solvent (coupling constant) is desired.
As noted above, fix {langevin} does not update the coordinates or
velocities of its atoms, only the forces. It is normally used with a
"fix nve"_fix_nve.html that does the time integration. Fix {langevin}
@ -136,7 +145,10 @@ This fix is not invoked during "energy minimization"_minimize.html.
"fix nvt"_fix_nvt.html, "fix temp/rescale"_fix_temp_rescale.html, "fix
viscous"_fix_viscous.html
[Default:] none
[Default:]
The option defaults are axes = 1 1 1, scale = 1.0 for all types, no
region, and weight = 1.0.
:link(Dunweg)
[(Dunweg)] Dunweg and Paul, Int J of Modern Physics C, 2, 817-27 (1991).