forked from lijiext/lammps
54 lines
1.6 KiB
Plaintext
54 lines
1.6 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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compute epair/atom command :h3
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[Syntax:]
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compute ID group-ID epair/atom :pre
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ID, group-ID are documented in "compute"_compute.html command
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epair/atom = style name of this compute command :ul
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[Examples:]
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compute 1 all epair/atom :pre
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[Description:]
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Define a computation that computes the per-atom pairwise energy for
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each atom in a group.
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The pairwise energy for each atom is computed by looping over its
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neighbors and computing the energy associated with the defined
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"pair_style"_pair_style.html command for each I,J pair (divided by 2).
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Thus the sum of per-atom energy for all atoms should give the total
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pairwise energy of the system.
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If two atoms interact and only one of them is in the compute group,
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the energy of the pairwise interaction is included in the per-atom
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energy of the atom in the group.
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For force fields that include a contribution to the pairwise energy
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that is computed as part of dihedral terms (i.e. 1-4 interactions),
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this contribution is NOT included in the per-atom pairwise energy.
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Computation of per-atom pairwise energy requires a loop thru the
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neighbor list and inter-processor communication, so it can be
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inefficient to compute/dump this quantity too frequently or to have
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multiple compute/dump commands, each of a {epair/atom} style.
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[Restrictions:]
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Some pair potentials do not allow the calculation of per-atom energy
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via this command. An error will be generated if this is the case.
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[Related commands:] none
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[Default:] none
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