lammps/doc/compute_pe.txt

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"LAMMPS WWW Site"_lws - "LAMMPS Documentation"_ld - "LAMMPS Commands"_lc :c
:link(lws,http://lammps.sandia.gov)
:link(ld,Manual.html)
:link(lc,Section_commands.html#comm)
:line
compute pe command :h3
[Syntax:]
compute ID group-ID pe keyword ... :pre
ID, group-ID are documented in "compute"_compute.html command
pe = style name of this compute command
zero of more keywords may be appended
keyword = {pair} or {bond} or {angle} or {dihedral} or {improper} or {kspace} :ul
[Examples:]
compute 1 all pe
compute molPE all bond angle dihedral improper :pre
[Description:]
Define a computation that calculates the potential energy of the
entire system of atoms. The specified group must be "all". See the
"compute epair/atom"_compute_epair_atom.html "compute
ebond/atom"_compute_ebond_atom.html or commands if you want per-atom
energies. These per-atom values could be summed for a group of atoms
via the "compute sum"_compute_sum.html command.
The energy is calulated by the various pair, bond, etc potentials
defined for the simulation. If no extra keywords are listed, then the
potential energy is the sum of pair, bond, angle, dihedral, improper,
and kspace (long-range) energy. If any extra keywords are listed,
then only those components are summed to compute the potential energy.
Various fixes can contribute to the total potential energy of the
system. See the doc pages for "individual fixes"_fix.html for
details. The {thermo} option of the
"compute_modify"_compute_modify.html command determines whether these
contributions are added into the computed potential energy. If no
keywords are specified the default is {yes}. If any keywords are
specified, the default is {no}.
A compute of this style with the ID of "thermo_pe" is created when
LAMMPS starts up, as if this command were in the input script:
compute thermo_pe all pe :pre
See the "thermo_style" command for more details.
[Restrictions:] none
[Related commands:] none
[Default:] none