forked from lijiext/lammps
109 lines
3.7 KiB
Plaintext
109 lines
3.7 KiB
Plaintext
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"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
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:link(lws,http://lammps.sandia.gov)
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:link(ld,Manual.html)
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:link(lc,Section_commands.html#comm)
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:line
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pair_style brownian command :h3
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pair_style brownian/poly command :h3
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[Syntax:]
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pair_style style mu flaglog flagfld cutinner cutoff t_target seed :pre
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style = {brownian} or {brownian/poly}
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mu = dynamic viscosity (dynamic viscosity units)
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flaglog = 0/1 log terms in the lubrication approximation on/off
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flagfld = 0/1 to include/exclude Fast Lubrication Dynamics effects
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cutinner = inner cutoff distance (distance units)
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cutoff = outer cutoff for interactions (distance units)
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t_target = target temp of the system (temperature units)
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seed = seed for the random number generator (positive integer) :ul
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[Examples:]
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pair_style brownian 1.5 1 1 2.01 2.5 2.0 5878567 (assuming radius=1)
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pair_coeff 1 1 2.05 2.8
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pair_coeff * * :pre
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[Description:]
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Styles {brownian} and {brownain/poly} compute Brownian forces and
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torques on finite-size particles. The former requires monodisperse
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spherical particles; the latter allows for polydisperse spherical
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particles.
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These pair styles are designed to be used with either the "pair_style
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lubricate"_pair_lubricate.html or "pair_style
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lubricateU"_pair_lubricateU.html commands to provide thermostatting
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when dissipative lubrication forces are acting. Thus the parameters
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{mu}, {flaglog}, {flagfld}, {cutinner}, and {cutoff} should be
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specified consistent with the settings in the lubrication pair styles.
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For details, refer to either of the lubrication pair styles.
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The {t_target} setting is used to specify the target temperature of
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the system. The random number {seed} is used to generate random
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numbers for the thermostatting procedure.
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The following coefficients must be defined for each pair of atoms
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types via the "pair_coeff"_pair_coeff.html command as in the examples
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above, or in the data file or restart files read by the
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"read_data"_read_data.html or "read_restart"_read_restart.html
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commands, or by mixing as described below:
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cutinner (distance units)
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cutoff (distance units) :ul
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The two coefficients are optional. If neither is specified, the two
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cutoffs specified in the pair_style command are used. Otherwise both
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must be specified.
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:line
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[Mixing, shift, table, tail correction, restart, rRESPA info]:
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For atom type pairs I,J and I != J, the two cutoff distances for this
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pair style can be mixed. The default mix value is {geometric}. See
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the "pair_modify" command for details.
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This pair style does not support the "pair_modify"_pair_modify.html
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shift option for the energy of the pair interaction.
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The "pair_modify"_pair_modify.html table option is not relevant
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for this pair style.
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This pair style does not support the "pair_modify"_pair_modify.html
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tail option for adding long-range tail corrections to energy and
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pressure.
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This pair style writes its information to "binary restart
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files"_restart.html, so pair_style and pair_coeff commands do not need
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to be specified in an input script that reads a restart file.
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This pair style can only be used via the {pair} keyword of the
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"run_style respa"_run_style.html command. It does not support the
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{inner}, {middle}, {outer} keywords.
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:line
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[Restrictions:]
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These styles are part of the FLD package. They are only enabled if
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LAMMPS was built with that package. See the "Making
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LAMMPS"_Section_start.html#2_3 section for more info.
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Only spherical monodisperse particles are allowed for pair_style
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brownian.
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Only spherical particles are allowed for pair_style brownian/poly.
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[Related commands:]
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"pair_coeff"_pair_coeff.html, "pair_style
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lubricate"_pair_lubricate.html, "pair_style
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lubricateU"_pair_lubricateU.html
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[Default:] none
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