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doc/fix_atom_swap.html
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@ -9,153 +9,137 @@
<HR> <HR>
<H3>fix atom/swap command <H3>fix atom_swap command
</H3> </H3>
<P><B>Syntax:</B> <P><B>Syntax:</B>
</P> </P>
<PRE>fix ID group-ID atom/swap N X type_1 type_2 seed T keyword values ... <PRE>fix ID group-ID atom_swap N X seed T keyword values ...
</PRE> </PRE>
<UL><LI>ID, group-ID are documented in <A HREF = "fix.html">fix</A> command <UL><LI>ID, group-ID are documented in <A HREF = "fix.html">fix</A> command
<LI>atom/swap = style name of this fix command <LI>atom_swap = style name of this fix command
<LI>N = invoke this fix every N steps <LI>N = invoke this fix every N steps
<LI>X = number of swaps to attempt every N steps <LI>X = number of swaps to attempt every N steps
<LI>type_1 = first atom type to swap
<LI>type_2 = second atom type to swap
<LI>seed = random # seed (positive integer) <LI>seed = random # seed (positive integer)
<LI>T = scaling temperature of the MC swaps (temperature units) <LI>T = scaling temperature of the MC swaps (temperature units)
<LI>zero or more keyword/value pairs may be appended to args <LI>one or more keyword/value pairs may be appended to args
<LI>keyword = <I>ke</I> or <I>semi-grand</I> or <I>region</I> <LI>keyword = <I>types</I> or <I>delta_mu</I> or <I>ke</I> or <I>semi-grand</I> or <I>region</I>
<PRE> <I>ke</I> value = <I>no</I> or <I>yes</I> <PRE> <I>types</I> values = two or more atom types
<I>delta_mu</I> values = number_of_types-1 relative chemical potentials
<I>ke</I> value = <I>no</I> or <I>yes</I>
<I>no</I> = no conservation of kinetic energy after atom swaps <I>no</I> = no conservation of kinetic energy after atom swaps
<I>yes</I> = kinetic energy is conserved after atom swaps <I>yes</I> = kinetic energy is conserved after atom swaps
<I>semi-grand</I> value = <I>no</I> or <I>yes</I> <I>semi-grand</I> value = <I>no</I> or <I>yes</I>
<I>no</I> = particle type counts and fractions conserved <I>no</I> = particle type counts and fractions conserved
<I>yes</I> = semi-grand canonical ensemble, particle fractions not conserved <I>yes</I> = semi-grand canonical ensemble, particle fractions not conserved
<I>region</I> value = region-ID <I>region</I> value = region-ID
region-ID = ID of region to use as a swap volume region-ID = ID of region to use as an exchange/move volume
</PRE> </PRE>
</UL> </UL>
<P><B>Examples:</B> <P><B>Examples:</B>
</P> </P>
<PRE>fix 2 all atom/swap 1 1 1 2 29494 300.0 ke no <PRE>fix 2 all atom/swap 1 1 29494 300.0 ke no types 1 2
fix atom_swap_fix all atom/swap 100 1 5 6 12345 298.0 region my_swap_region fix atom_swap_fix all atom/swap 100 1 12345 298.0 region my_swap_region types 5 6
fix SGMC all atom/swap 1 100 345 1.0 semi-grand yes types 1 2 3 delta_mu 4.3 -5.0
</PRE> </PRE>
<P><B>Description:</B> <P><B>Description:</B>
</P> </P>
<P>This fix performs Monte Carlo swaps of atoms of one type with atoms of <P>This fix performs Monte Carlo swaps of atoms of one given atom type with atoms
a second type. The specified temperature <I>T</I> is used to scale the of the other given atom types. The specified T is used in the Metropolis criterion
energy in the criterion for accepting or rejecting each swap. The fix dictating swap probabilities.
is invoked once every <I>N</I> steps. Each time the fix is invoked <I>X</I>
swap attempts are made, one after the other, bewteen pairs of randomly
selected atoms. Two attributes of the atoms in the pair are swapped:
the atom type and the atom charge (if defined). Each attempted swap
is accepted or rejected based on the Metropolis criterion using the
Boltzmann factor exp(-Edelta / kT), where Edelta is the change in the
system potential energy due to the swap, k is the Boltzmann constant,
and <I>T</I> is the specified temperature.
</P> </P>
<P>In addition to the MC swaps, atoms in the simulation domain will move <P>Perform X swaps of atoms of one type with atoms of another type according to a
via normal dynamic timestepping if a time integration fix is defined, Monte Carlo probability. Swap candidates must be in the fix group, must be in
e.g. <A HREF = "fix_nvt.html">fix_nvt</A>, which will result in a hybrid MC+MD the region (if specified), and must be of one of the listed types. Swaps are
simulation. If a swap produces a poorly equilibrated system, a attempted between candidates that are chosen randomly with equal probability
smaller-than-usual timestep size may be needed when running such a among the candidate atoms. Swaps are not attempted between atoms of the same
simulation. type since nothing would happen.
</P> </P>
<P>The <I>ke</I> keyword can be set to <I>no</I> to turn off kinetic energy <P>All atoms in the simulation domain can be moved using regular time
conservation for swaps. The default is <I>yes</I>, which means that swapped integration displacements, e.g. via <A HREF = "fix_nvt.html">fix_nvt</A>, resulting
atoms have their velocities scaled by the ratio of the masses of the in a hybrid MC+MD simulation. A smaller-than-usual timestep size
swapped atom types. This ensures that the kinetic energy of each atom may be needed when running such a hybrid simulation, especially if
is the same after the swap as it was before the swap, even though the the swapped atoms are not well equilibrated.
atom masses have changed. </P>
<P>The <I>types</I> keyword is required. At least two atom types must be specified.
</P>
<P>The <I>ke</I> keyword can be set to <I>no</I> to turn off kinetic energy conservation
for swaps. The default is <I>yes</I>, which means that swapped atoms have their
velocities scaled by the ratio of the masses of the swapped atom types. This
ensures that the kinetic energy of each atom is the same after the swap as it
was before the swap, even though the atom masses have changed.
</P> </P>
<P>The <I>semi-grand</I> keyword can be set to <I>yes</I> to switch to the semi-grand <P>The <I>semi-grand</I> keyword can be set to <I>yes</I> to switch to the semi-grand
canonical ensemble, meaning that the total number of each particle type canonical ensemble, meaning that the total number of each particle type
does not need to be conserved. The default is <I>no</I>, which means that the does not need to be conserved. The default is <I>no</I>, which means that the
only kind of swap allowed exchanges an atom of type_1 with an atom of type_2. only kind of swap allowed exchanges an atom of one type with an atom of a
In other words, the relative mole fractions of the swapped atoms remains different given type. In other words, the relative mole fractions of the
constant. Whereas in the semi-grand canonical ensemble, the composition of swapped atoms remains constant. Whereas in the semi-grand canonical ensemble,
the system can change. Particles of type_1 can independently be converted the composition of the system can change. Note that when using <I>semi-grand</I>,
to type_2, and particles of type_2 can independently be converted to type_1. all atoms in the fix group are eligible for attempted conversion to one of
Swaps in each direction are attempted half of the time. the given types, even if its current type is not one of the given types.
An attempt is made to switch the selected atom to one of the listed
<I>types</I> with equal probability. Acceptance of each attempt depends upon the
Metropolis criterion.
</P> </P>
<P>If the <I>region</I> keyword is not used, all atoms of <I>type_1</I> and <P>The <I>delta_mu</I> keyword allows users to specify non-zero chemical potentials
<I>type_2</I> which are in the specified group are candidates for swapping. for each of the atom types. All chemical potentials are relative to the first
If the <I>region</I> keyword is used, swappable atoms must also be in the atom type, so no value is given for the first atom type. These parameters are
specified region. Each time a swap is performed one random atom is useful for semi-grand canonical ensemble simulations where it may be
chosen from the list of candidate <I>type_1</I> atoms, and one random atom desirable to actively control the composition of the system. When given,
from the list of candidate <I>type_2</I> atoms. A pair of swapped atoms there must be ntypes-1 values given, where ntypes is the number of atom
can thus be far apart geometrically. If multiple swaps are attempted types in the simulated system. Note that a value for delta_mu is required for
in the same timestep, an individual atom may be swapped multiple all atom types when using <I>semi-grand</I>, even for atom types not listed
times. following the <I>types</I> keyword. This is because when using <I>semi-grand</I>, it is
possible that any of the atom types in the system could be part of the fix
group and therefore are eligible for swapping to one of the listed atom types.
</P> </P>
<P>An additional requirement for charged systems is that all swappable <P>This command may optionally use the <I>region</I> keyword to define
atoms of <I>type_1</I> must have the same charge, and likewise for <I>type_2</I>. swap volume. The specified region must have been
Atoms of <I>type_1</I> need not have the same charge as atoms of <I>type_2</I>. previously defined with a <A HREF = "region.html">region</A> command. It must be
defined with side = <I>in</I>. Swap attempts occur only between atoms that
are both within the specified region. Swaps are not otherwise attempted.
</P> </P>
<P>Note that this fix computes total potential energies before and after <P>You should ensure you do not swap atoms belonging to a molecule, or
attempted swaps, so even systems with complicated potential energy LAMMPS will soon generate an error when it tries to find those atoms.
calculations can be used, including the following: LAMMPS will warn you if any of the atoms eligible for swapping have a
non-zero molecule ID, but does not check for this at the time of
swapping.
</P> </P>
<UL><LI>long-range electrostatics (KSpace) <P>This fix checks to ensure all atoms of the given types have the same
<LI>many-body pair styles atomic charge. LAMMPS doesn't enforce this in general, but it is
<LI>hybrid pair styles needed for this fix to simplify the swapping procedure. Successful swaps
<LI>EAM pair styles will swap the atom type and charge of the swapped atoms.
<LI>triclinic systems </P>
<P>Since this fix computes total potential energies before and after
proposed swaps, so even complicated potential energy calculations are
OK, including the following:
</P>
<UL><LI> long-range electrostatics (kspace)
<LI> many body pair styles
<LI> hybrid pair styles
<LI> eam pair styles
<LI> triclinic systems
<LI> need to include potential energy contributions from other fixes
</UL> </UL>
<P>Some fixes have an associated potential energy. Currently, the <P>Some fixes have an associated potential energy. Examples of such fixes
potential energy contribution due to these fixes is not included in include: <A HREF = "fix_efield.html">efield</A>, <A HREF = "fix_gravity.html">gravity</A>,
the Metropolis criterion dictating atom swap probabilities. Examples <A HREF = "fix_addforce.html">addforce</A>, <A HREF = "fix_langevin.html">langevin</A>,
of such fixes include: <A HREF = "fix_efield.html">efield</A>, <A HREF = "fix_restrain.html">restrain</A>, <A HREF = "fix_temp_berendsen.html">temp/berendsen</A>,
<A HREF = "fix_gravity.html">gravity</A>, <A HREF = "fix_addforce.html">addforce</A>, <A HREF = "fix_temp_rescale.html">temp/rescale</A>, and <A HREF = "fix_wall.html">wall fixes</A>.
<A HREF = "fix_restrain.html">restrain</A>, and <A HREF = "fix_wall.html">wall fixes</A>. For that energy to be included in the total potential energy of the
</P> system (the quantity used when performing GCMC moves),
<P>IMPORTANT NOTE: During the swaps performed within a single timestep, you MUST enable the <A HREF = "fix_modify.html">fix_modify</A> <I>energy</I> option for
this fix performs minimal communication to update the state of the that fix. The doc pages for individual <A HREF = "fix.html">fix</A> commands
system. If the cutoff distance for all type pairs, as defined by the specify if this should be done.
<A HREF = "pair_style.html">pair_style</A> is the same, the neighbor list does not
need to be rebuilt when a swap takes place. The CPU cost per swap
will then be equivalent to roughly a single MD timestep. If the
cutoff distances are not the same for all type pairs, then the
neighbor list will be rebuilt, and the CPU cost per swap will be
higher.
</P>
<HR>
<P>IMPORTANT NOTE: If you only wish to use this fix to relax a system
without dynamics, e.g. to model surface segregation in an alloy, then
you do not need to define a time integration fix. In this scenario an
MC-only simulation can be run in a single timestep or multiple
timesteps as follows:
</P>
<PRE>fix mc all atom/swap 1 100000 ...
run 1
</PRE>
<P>or
</P>
<PRE>fix mc all atom/swap 1 1000 ...
run 100
</PRE>
<P>In the first case, 100000 swaps are attempted in the first (only)
timestep. A neighbor list will only be built once, which is
sufficient since atoms are not moving.
</P>
<P>In the second case, the same 100000 swaps are spread across 100
timesteps. This will require 100 neighbor list builds (once each time
the fix is invoked, which should still be relatively cheap), but also
allows you to monitor or analyze various quantities such as the
evolution of the system energy as a function of timestep, as if the
system were evolving over time.
</P> </P>
<P><B>Restart, fix_modify, output, run start/stop, minimize info:</B> <P><B>Restart, fix_modify, output, run start/stop, minimize info:</B>
</P> </P>
@ -190,13 +174,15 @@ LAMMPS</A> section for more info.
</P> </P>
<P><B>Related commands:</B> <P><B>Related commands:</B>
</P> </P>
<P><A HREF = "fix_bond_swap.html">fix bond/swap</A>, <A HREF = "fix_nvt.html">fix_nvt</A>, <P><A HREF = "fix_nvt.html">fix_nvt</A>, <A HREF = "neighbor.html">neighbor</A>,
<A HREF = "neighbor.html">neighbor</A>, <A HREF = "fix_deposit.html">fix_deposit</A>, <A HREF = "fix_deposit.html">fix_deposit</A>, <A HREF = "fix_evaporate.html">fix_evaporate</A>,
<A HREF = "fix_evaporate.html">fix_evaporate</A>, <A HREF = "delete_atoms.html">delete_atoms</A>, <A HREF = "delete_atoms.html">delete_atoms</A>, <A HREF = "fix_gcmc.html">fix_gcmc</A>
<A HREF = "fix_gcmc.html">fix_gcmc</A>
</P> </P>
<P><B>Default:</B> <P><B>Default:</B>
</P> </P>
<P>The option defaults are ke = yes, semi-grand = no. <P>The option defaults are ke = yes, semi-grand = no, delta_mu = 0.0 for
all atom types.
</P> </P>
<HR>
</HTML> </HTML>

198
doc/fix_atom_swap.txt
View File

@ -6,22 +6,22 @@
:line :line
fix atom/swap command :h3 fix atom_swap command :h3
[Syntax:] [Syntax:]
fix ID group-ID atom/swap N X type_1 type_2 seed T keyword values ... :pre fix ID group-ID atom_swap N X seed T keyword values ... :pre
ID, group-ID are documented in "fix"_fix.html command :ulb,l ID, group-ID are documented in "fix"_fix.html command :ulb,l
atom/swap = style name of this fix command :l atom_swap = style name of this fix command :l
N = invoke this fix every N steps :l N = invoke this fix every N steps :l
X = number of swaps to attempt every N steps :l X = number of swaps to attempt every N steps :l
type_1 = first atom type to swap :l
type_2 = second atom type to swap :l
seed = random # seed (positive integer) :l seed = random # seed (positive integer) :l
T = scaling temperature of the MC swaps (temperature units) :l T = scaling temperature of the MC swaps (temperature units) :l
zero or more keyword/value pairs may be appended to args :l one or more keyword/value pairs may be appended to args :l
keyword = {ke} or {semi-grand} or {region} :l keyword = {types} or {delta_mu} or {ke} or {semi-grand} or {region} :l
{types} values = two or more atom types
{delta_mu} values = number_of_types-1 relative chemical potentials
{ke} value = {no} or {yes} {ke} value = {no} or {yes}
{no} = no conservation of kinetic energy after atom swaps {no} = no conservation of kinetic energy after atom swaps
{yes} = kinetic energy is conserved after atom swaps {yes} = kinetic energy is conserved after atom swaps
@ -29,119 +29,105 @@ keyword = {ke} or {semi-grand} or {region} :l
{no} = particle type counts and fractions conserved {no} = particle type counts and fractions conserved
{yes} = semi-grand canonical ensemble, particle fractions not conserved {yes} = semi-grand canonical ensemble, particle fractions not conserved
{region} value = region-ID {region} value = region-ID
region-ID = ID of region to use as a swap volume :pre region-ID = ID of region to use as an exchange/move volume :pre
:ule :ule
[Examples:] [Examples:]
fix 2 all atom/swap 1 1 1 2 29494 300.0 ke no fix 2 all atom/swap 1 1 29494 300.0 ke no types 1 2
fix atom_swap_fix all atom/swap 100 1 5 6 12345 298.0 region my_swap_region :pre fix atom_swap_fix all atom/swap 100 1 12345 298.0 region my_swap_region types 5 6
fix SGMC all atom/swap 1 100 345 1.0 semi-grand yes types 1 2 3 delta_mu 4.3 -5.0 :pre
[Description:] [Description:]
This fix performs Monte Carlo swaps of atoms of one type with atoms of This fix performs Monte Carlo swaps of atoms of one given atom type with atoms
a second type. The specified temperature {T} is used to scale the of the other given atom types. The specified T is used in the Metropolis criterion
energy in the criterion for accepting or rejecting each swap. The fix dictating swap probabilities.
is invoked once every {N} steps. Each time the fix is invoked {X}
swap attempts are made, one after the other, bewteen pairs of randomly
selected atoms. Two attributes of the atoms in the pair are swapped:
the atom type and the atom charge (if defined). Each attempted swap
is accepted or rejected based on the Metropolis criterion using the
Boltzmann factor exp(-Edelta / kT), where Edelta is the change in the
system potential energy due to the swap, k is the Boltzmann constant,
and {T} is the specified temperature.
In addition to the MC swaps, atoms in the simulation domain will move Perform X swaps of atoms of one type with atoms of another type according to a
via normal dynamic timestepping if a time integration fix is defined, Monte Carlo probability. Swap candidates must be in the fix group, must be in
e.g. "fix_nvt"_fix_nvt.html, which will result in a hybrid MC+MD the region (if specified), and must be of one of the listed types. Swaps are
simulation. If a swap produces a poorly equilibrated system, a attempted between candidates that are chosen randomly with equal probability
smaller-than-usual timestep size may be needed when running such a among the candidate atoms. Swaps are not attempted between atoms of the same
simulation. type since nothing would happen.
The {ke} keyword can be set to {no} to turn off kinetic energy All atoms in the simulation domain can be moved using regular time
conservation for swaps. The default is {yes}, which means that swapped integration displacements, e.g. via "fix_nvt"_fix_nvt.html, resulting
atoms have their velocities scaled by the ratio of the masses of the in a hybrid MC+MD simulation. A smaller-than-usual timestep size
swapped atom types. This ensures that the kinetic energy of each atom may be needed when running such a hybrid simulation, especially if
is the same after the swap as it was before the swap, even though the the swapped atoms are not well equilibrated.
atom masses have changed.
The {types} keyword is required. At least two atom types must be specified.
The {ke} keyword can be set to {no} to turn off kinetic energy conservation
for swaps. The default is {yes}, which means that swapped atoms have their
velocities scaled by the ratio of the masses of the swapped atom types. This
ensures that the kinetic energy of each atom is the same after the swap as it
was before the swap, even though the atom masses have changed.
The {semi-grand} keyword can be set to {yes} to switch to the semi-grand The {semi-grand} keyword can be set to {yes} to switch to the semi-grand
canonical ensemble, meaning that the total number of each particle type canonical ensemble, meaning that the total number of each particle type
does not need to be conserved. The default is {no}, which means that the does not need to be conserved. The default is {no}, which means that the
only kind of swap allowed exchanges an atom of type_1 with an atom of type_2. only kind of swap allowed exchanges an atom of one type with an atom of a
In other words, the relative mole fractions of the swapped atoms remains different given type. In other words, the relative mole fractions of the
constant. Whereas in the semi-grand canonical ensemble, the composition of swapped atoms remains constant. Whereas in the semi-grand canonical ensemble,
the system can change. Particles of type_1 can independently be converted the composition of the system can change. Note that when using {semi-grand},
to type_2, and particles of type_2 can independently be converted to type_1. all atoms in the fix group are eligible for attempted conversion to one of
Swaps in each direction are attempted half of the time. the given types, even if its current type is not one of the given types.
An attempt is made to switch the selected atom to one of the listed
{types} with equal probability. Acceptance of each attempt depends upon the
Metropolis criterion.
If the {region} keyword is not used, all atoms of {type_1} and The {delta_mu} keyword allows users to specify non-zero chemical potentials
{type_2} which are in the specified group are candidates for swapping. for each of the atom types. All chemical potentials are relative to the first
If the {region} keyword is used, swappable atoms must also be in the atom type, so no value is given for the first atom type. These parameters are
specified region. Each time a swap is performed one random atom is useful for semi-grand canonical ensemble simulations where it may be
chosen from the list of candidate {type_1} atoms, and one random atom desirable to actively control the composition of the system. When given,
from the list of candidate {type_2} atoms. A pair of swapped atoms there must be ntypes-1 values given, where ntypes is the number of atom
can thus be far apart geometrically. If multiple swaps are attempted types in the simulated system. Note that a value for delta_mu is required for
in the same timestep, an individual atom may be swapped multiple all atom types when using {semi-grand}, even for atom types not listed
times. following the {types} keyword. This is because when using {semi-grand}, it is
possible that any of the atom types in the system could be part of the fix
group and therefore are eligible for swapping to one of the listed atom types.
An additional requirement for charged systems is that all swappable This command may optionally use the {region} keyword to define
atoms of {type_1} must have the same charge, and likewise for {type_2}. swap volume. The specified region must have been
Atoms of {type_1} need not have the same charge as atoms of {type_2}. previously defined with a "region"_region.html command. It must be
defined with side = {in}. Swap attempts occur only between atoms that
are both within the specified region. Swaps are not otherwise attempted.
Note that this fix computes total potential energies before and after You should ensure you do not swap atoms belonging to a molecule, or
attempted swaps, so even systems with complicated potential energy LAMMPS will soon generate an error when it tries to find those atoms.
calculations can be used, including the following: LAMMPS will warn you if any of the atoms eligible for swapping have a
non-zero molecule ID, but does not check for this at the time of
swapping.
long-range electrostatics (KSpace) This fix checks to ensure all atoms of the given types have the same
many-body pair styles atomic charge. LAMMPS doesn't enforce this in general, but it is
hybrid pair styles needed for this fix to simplify the swapping procedure. Successful swaps
EAM pair styles will swap the atom type and charge of the swapped atoms.
triclinic systems :ul
Some fixes have an associated potential energy. Currently, the Since this fix computes total potential energies before and after
potential energy contribution due to these fixes is not included in proposed swaps, so even complicated potential energy calculations are
the Metropolis criterion dictating atom swap probabilities. Examples OK, including the following:
of such fixes include: "efield"_fix_efield.html,
"gravity"_fix_gravity.html, "addforce"_fix_addforce.html,
"restrain"_fix_restrain.html, and "wall fixes"_fix_wall.html.
IMPORTANT NOTE: During the swaps performed within a single timestep, long-range electrostatics (kspace)
this fix performs minimal communication to update the state of the many body pair styles
system. If the cutoff distance for all type pairs, as defined by the hybrid pair styles
"pair_style"_pair_style.html is the same, the neighbor list does not eam pair styles
need to be rebuilt when a swap takes place. The CPU cost per swap triclinic systems
will then be equivalent to roughly a single MD timestep. If the need to include potential energy contributions from other fixes :ul
cutoff distances are not the same for all type pairs, then the
neighbor list will be rebuilt, and the CPU cost per swap will be
higher.
:line Some fixes have an associated potential energy. Examples of such fixes
include: "efield"_fix_efield.html, "gravity"_fix_gravity.html,
IMPORTANT NOTE: If you only wish to use this fix to relax a system "addforce"_fix_addforce.html, "langevin"_fix_langevin.html,
without dynamics, e.g. to model surface segregation in an alloy, then "restrain"_fix_restrain.html, "temp/berendsen"_fix_temp_berendsen.html,
you do not need to define a time integration fix. In this scenario an "temp/rescale"_fix_temp_rescale.html, and "wall fixes"_fix_wall.html.
MC-only simulation can be run in a single timestep or multiple For that energy to be included in the total potential energy of the
timesteps as follows: system (the quantity used when performing GCMC moves),
you MUST enable the "fix_modify"_fix_modify.html {energy} option for
fix mc all atom/swap 1 100000 ... that fix. The doc pages for individual "fix"_fix.html commands
run 1 :pre specify if this should be done.
or
fix mc all atom/swap 1 1000 ...
run 100 :pre
In the first case, 100000 swaps are attempted in the first (only)
timestep. A neighbor list will only be built once, which is
sufficient since atoms are not moving.
In the second case, the same 100000 swaps are spread across 100
timesteps. This will require 100 neighbor list builds (once each time
the fix is invoked, which should still be relatively cheap), but also
allows you to monitor or analyze various quantities such as the
evolution of the system energy as a function of timestep, as if the
system were evolving over time.
[Restart, fix_modify, output, run start/stop, minimize info:] [Restart, fix_modify, output, run start/stop, minimize info:]
@ -176,11 +162,13 @@ LAMMPS"_Section_start.html#start_3 section for more info.
[Related commands:] [Related commands:]
"fix bond/swap"_fix_bond_swap.html, "fix_nvt"_fix_nvt.html, "fix_nvt"_fix_nvt.html, "neighbor"_neighbor.html,
"neighbor"_neighbor.html, "fix_deposit"_fix_deposit.html, "fix_deposit"_fix_deposit.html, "fix_evaporate"_fix_evaporate.html,
"fix_evaporate"_fix_evaporate.html, "delete_atoms"_delete_atoms.html, "delete_atoms"_delete_atoms.html, "fix_gcmc"_fix_gcmc.html
"fix_gcmc"_fix_gcmc.html
[Default:] [Default:]
The option defaults are ke = yes, semi-grand = no. The option defaults are ke = yes, semi-grand = no, delta_mu = 0.0 for
all atom types.
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