forked from lijiext/lammps
73 lines
2.0 KiB
Plaintext
73 lines
2.0 KiB
Plaintext
"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 dpd/conservative command :h3
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[Syntax:]
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pair_style dpd/conservative cutoff :pre
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cutoff = global cutoff for DPD interactions (distance units) :ul
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[Examples:]
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pair_style dpd/conservative 2.5
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pair_coeff * * 3.0 2.5
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pair_coeff 1 1 3.0 :pre
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[Description:]
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Style {dpd/conservative} computes the conservative force for
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dissipative particle dynamics (DPD). The conservative force on atom I
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due to atom J is given by
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:c,image(Eqs/pair_dpd_conservative.jpg)
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where the weighting factor, omega_ij, varies between 0 and 1, and is
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chosen to have the following functional form:
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:c,image(Eqs/pair_dpd_omega.jpg)
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where Rij is a unit vector in the direction Ri - Rj, and Rc is the
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cutoff. Note that alternative definitions of the weighting function
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exist, but would have to be implemented as a separate pair style
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command.
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Style {dpd/conservative} differs from the other dpd styles in that the
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dissipative and random forces are not computed within the pair style.
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For style {dpd/conservative}, the pairwise energy is due only to the
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conservative force term Fc, and is shifted to be zero at the cutoff
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distance Rc. The pairwise virial is calculated using only the
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conservative term.
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Style {dpd/conservative} requires the following coefficients to be
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defined for each pair of atoms types via the
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"pair_coeff"_pair_coeff.html command as in the examples above, or in
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the data file or restart files read by the "read_data"_read_data.html
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or "read_restart"_read_restart.html commands:
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A (force units)
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cutoff (distance units) :ul
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The last coefficient is optional. If not specified, the global DPD
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cutoff is used.
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:line
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[Restrictions:]
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The pair style {dpd/conservative} is only available if LAMMPS is built
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with the USER-DPD package.
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[Related commands:]
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"pair_coeff"_pair_coeff.html, "pair_dpd"_pair_dpd.html
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[Default:] none
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