git-svn-id: svn://svn.icms.temple.edu/lammps-ro/trunk@4652 f3b2605a-c512-4ea7-a41b-209d697bcdaa

This commit is contained in:
sjplimp 2010-09-01 20:17:25 +00:00
parent d6a892f246
commit ed40d27145
6 changed files with 41 additions and 31 deletions

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@ -135,6 +135,7 @@ commands)
charged pairwise potentials: Coulombic, point-dipole charged pairwise potentials: Coulombic, point-dipole
manybody potentials: EAM, Finnis/Sinclair EAM, modified EAM (MEAM), \ manybody potentials: EAM, Finnis/Sinclair EAM, modified EAM (MEAM), \
embedded ion method (EIM), Stillinger-Weber, Tersoff, AI-REBO, ReaxFF, COMB embedded ion method (EIM), Stillinger-Weber, Tersoff, AI-REBO, ReaxFF, COMB
electron force field (eFF)
coarse-grained potentials: DPD, GayBerne, REsquared, colloidal, DLVO coarse-grained potentials: DPD, GayBerne, REsquared, colloidal, DLVO
mesoscopic potentials: granular, Peridynamics mesoscopic potentials: granular, Peridynamics
bond potentials: harmonic, FENE, Morse, nonlinear, class 2, \ bond potentials: harmonic, FENE, Morse, nonlinear, class 2, \

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@ -22,16 +22,17 @@ compute myTemp all temp/deform/eff :pre
[Description:] [Description:]
Define a computation that calculates the temperature of a group of Define a computation that calculates the temperature of a group of
nuclei and electrons using the electron force field, after subtracting nuclei and electrons in the "electron force field"_pair_eff.html
out a streaming velocity induced by the simulation box changing size model, after subtracting out a streaming velocity induced by the
and/or shape, for example in a non-equilibrium MD (NEMD) simulation. simulation box changing size and/or shape, for example in a
The size/shape change is induced by use of the "fix non-equilibrium MD (NEMD) simulation. The size/shape change is
deform/eff"_fix_deform_eff.html command. A compute of this style is induced by use of the "fix deform/eff"_fix_deform_eff.html command. A
created by the "fix nvt/sllod/eff"_fix_nvt_sllod_eff.html command to compute of this style is created by the "fix
compute the thermal temperature of atoms for thermostatting purposes. nvt/sllod/eff"_fix_nvt_sllod_eff.html command to compute the thermal
A compute of this style can also be used by any command that computes temperature of atoms for thermostatting purposes. A compute of this
a temperature, e.g. "thermo_modify"_thermo_modify.html, "fix style can also be used by any command that computes a temperature,
npt/eff"_fix_nh.html, etc. e.g. "thermo_modify"_thermo_modify.html, "fix npt/eff"_fix_nh.html,
etc.
The calculation performed by this compute is exactly like that The calculation performed by this compute is exactly like that
described by the "compute temp/deform"_compute_temp_deform.html described by the "compute temp/deform"_compute_temp_deform.html

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@ -23,9 +23,10 @@ compute mine flow temp/region/eff boundary :pre
[Description:] [Description:]
Define a computation that calculates the temperature of a group of Define a computation that calculates the temperature of a group of
nuclei and electrons wihtin a geometric region using the electron nuclei and electrons in the "electron force field"_pair_eff.html
force field. A compute of this style can be used by commands that model, within a geometric region using the electron force field. A
compute a temperature, e.g. "thermo_modify"_thermo_modify.html. compute of this style can be used by commands that compute a
temperature, e.g. "thermo_modify"_thermo_modify.html.
The operation of this compute is exactly like that described by the The operation of this compute is exactly like that described by the
"compute temp/region"_compute_temp_region.html command, where the "compute temp/region"_compute_temp_region.html command, where the

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@ -60,7 +60,10 @@ interactions (<A HREF = "pair_style.html">pair_style</A>).
<P>The Ff and Fr terms are added by this fix on a per-particle basis. <P>The Ff and Fr terms are added by this fix on a per-particle basis.
</P> </P>
<P>Ff is a frictional drag or viscous damping term proportional to the <P>Ff is a frictional drag or viscous damping term proportional to the
particle's velocity (including the electronic radial degrees of freedom). 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. particle's velocity (including the electronic radial degrees of
freedom). 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.
</P> </P>
<P>Fr is a force due to solvent atoms at a temperature T randomly bumping <P>Fr is a force due to solvent atoms at a temperature T randomly bumping
into the particle. As derived from the fluctuation/dissipation into the particle. As derived from the fluctuation/dissipation
@ -73,15 +76,18 @@ the direction and magnitude of this force as described in
a Gaussian random number) for speed. a Gaussian random number) for speed.
</P> </P>
<P>Note that the thermostat effect of this fix is applied to the <P>Note that the thermostat effect of this fix is applied to the
translational and electronic radial degrees of freedom for the particles in a system. The translational degrees of freedom can also have a bias translational and electronic radial degrees of freedom for the
velocity removed from them before thermostatting takes place; see the particles in a system. The translational degrees of freedom can also
description below. have a bias velocity removed from them before thermostatting takes
place; see the description below.
</P> </P>
<P>IMPORTANT NOTE: Unlike the <A HREF = "fix_nh_eff.html">fix nvt/eff</A> command which <P>IMPORTANT NOTE: Unlike the <A HREF = "fix_nh_eff.html">fix nvt/eff</A> command which
performs Nose/Hoover thermostatting AND time integration, this fix performs Nose/Hoover thermostatting AND time integration, this fix
does NOT perform time integration. It only modifies forces to effect does NOT perform time integration. It only modifies forces to effect
thermostatting. Thus you must use a separate time integration fix, thermostatting. Thus you must use a separate time integration fix,
like <A HREF = "fix_nve_eff.html">fix nve/eff</A> to actually update the velocities (including electronic radial velocities) and positions of atoms (nuclei and electrons) using the modified forces. Likewise, this fix like <A HREF = "fix_nve_eff.html">fix nve/eff</A> to actually update the velocities
(including electronic radial velocities) and positions of atoms
(nuclei and electrons) using the modified forces. Likewise, this fix
should not normally be used on atoms that also have their temperature should not normally be used on atoms that also have their temperature
controlled by another fix - e.g. by <A HREF = "fix_nh.html">fix nvt/eff</A> command. controlled by another fix - e.g. by <A HREF = "fix_nh.html">fix nvt/eff</A> command.
</P> </P>
@ -106,13 +112,14 @@ the remaining thermal degrees of freedom, and the bias is added back
in. in.
</P> </P>
<P>The <I>damp</I> parameter is specified in time units and determines how <P>The <I>damp</I> parameter is specified in time units and determines how
rapidly the temperature is relaxed. For example, a value of 0.1 rapidly the temperature is relaxed. For example, a value of 0.1 means
means to relax the temperature in a timespan of 100 timesteps (for the default 0.001 timesteps and fmsec unit used in eFF - see the <A HREF = "units.html">units</A> command). to relax the temperature in a timespan of 100 timesteps (for the
The damp factor can be thought of as inversely related to the default 0.001 timesteps and fmsec unit used in eFF - see the
viscosity of the solvent. I.e. a small relaxation time implies a <A HREF = "units.html">units</A> command). The damp factor can be thought of as
hi-viscosity solvent and vice versa. See the discussion about gamma inversely related to the viscosity of the solvent. I.e. a small
and viscosity in the documentation for the <A HREF = "fix_viscous.html">fix relaxation time implies a hi-viscosity solvent and vice versa. See
viscous</A> command for more details. the discussion about gamma and viscosity in the documentation for the
<A HREF = "fix_viscous.html">fix viscous</A> command for more details.
</P> </P>
<P>The random # <I>seed</I> must be a positive integer. A Marsaglia random <P>The random # <I>seed</I> must be a positive integer. A Marsaglia random
number generator is used. Each processor uses the input seed to number generator is used. Each processor uses the input seed to
@ -182,7 +189,7 @@ LAMMPS</A> section for more info.
</P> </P>
<P><B>Related commands:</B> <P><B>Related commands:</B>
</P> </P>
<P><A HREF = "fix_nh.html">fix nvt/eff</A> <P><A HREF = "fix_langevin.html">fix langevin</A>
</P> </P>
<P><B>Default:</B> <P><B>Default:</B>
</P> </P>

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@ -15,10 +15,10 @@
</P> </P>
<P>pair_style eff/cut cutoff eradius_limit_flag pressure_flag <P>pair_style eff/cut cutoff eradius_limit_flag pressure_flag
</P> </P>
<P>cutoff = global cutoff for Coulombic interactions <UL><LI>cutoff = global cutoff for Coulombic interactions
eradius_limit_flag = 0 or 1 for whether electron size is restrained (optional) <LI>eradius_limit_flag = 0 or 1 for whether electron size is restrained (optional)
pressure_flag = 0 or 1 to define the type of pressure calculation (optional) <LI>pressure_flag = 0 or 1 to define the type of pressure calculation (optional)
</P> </UL>
<P><B>Examples:</B> <P><B>Examples:</B>
</P> </P>
<PRE>pair_style eff/cut 39.7 <PRE>pair_style eff/cut 39.7

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@ -14,7 +14,7 @@ pair_style eff/cut cutoff eradius_limit_flag pressure_flag
cutoff = global cutoff for Coulombic interactions cutoff = global cutoff for Coulombic interactions
eradius_limit_flag = 0 or 1 for whether electron size is restrained (optional) eradius_limit_flag = 0 or 1 for whether electron size is restrained (optional)
pressure_flag = 0 or 1 to define the type of pressure calculation (optional) pressure_flag = 0 or 1 to define the type of pressure calculation (optional) :ul
[Examples:] [Examples:]