This directory contains potential files for different elements and
alloys, as used by LAMMPS for various pair styles. See the
description of the "pair_style" and "pair_coeff" commands for details
of the file formats and the various styles in LAMMPS that read these
files.
IMPORTANT NOTE: These files are provided primarily to demonstrate the
different types of interatomic potentials that LAMMPS supports. Each
file has a header line with a date for when it was added to the LAMMPS
distribution. Also a citation and contact info for the person who
contributed it to LAMMPS (if we remember who that is). This info is
not meant to "guarantee" that the potential is correct. I.e. that the
contributor transcribed the info from the paper correctly or that the
paper itself had no errors. In many cases (but not all), we or other
LAMMPS users have confirmed that when the potential file is used with
the current version of LAMMPS, it reproduces results in the cited
publication. In some cases, this accuracy check may require other
parameters not contained in the potential file to be specified as part
of a LAMMPS simulation, e.g. a distance cutoff. Also, for particular
materials and applications modeled with a pair style coded in LAMMPS,
a different potential file may be more suitable than the one provided
here. For best results when choosing a potential, you should do a
thorough search of published literature and on-line databases such as
the Interatomic Potentials Repository Project (NIST) or the
Knowledgebase of Interatomic Models (KIM). Whatever potential you
choose for your application, you should verify that you have defined
it and are using it correctly in LAMMPS, by comparing with published
results for that potential.
2nd IMPORTANT NOTE: The DATE field in the first line of each of these
files is printed to the screen and log file when it is read by a
LAMMPS input script. If an updated or corrected version of the same
potential file is later added to the LAMMPS distribution, then a new
DATE will be added to the file. This means you can "diff" an old and
new log file and see that the potential file changed, which could
affect your simulation results.
3rd IMPORTANT NOTE: The UNITS field in the first line of these files
is parsed and checked against the current units setting in LAMMPS.
If there is a mismatch, LAMMPS will stop with an error. If there is
no UNITS field provided, there is no check.
A small amount of metadata is included in the first line of each file
in order to track the provenance of each file. The metadata is
indicated by a keyword followed by white space, followed by the
metadata, followed by whitespace. The metadata is intended to be
straightforward and human-readable, while still conforming to a
standard format.
DATE: Format is "yyyy-mm-dd". This indicates the date of a significant
change to the file. Multiple entries can appear in reverse
chronological order. As described above, the first of these will be
printed to the screen and log file when it is read by a LAMMPS input
script.
UNITS: Format is "unit". This indicates the LAMMPS unit style this
potential was parameterized for. Any difference to the currently used
unit style in a LAMMPS simulation will cause termination with an error.
CONTRIBUTOR: Format is "name[, email address]". This indicates the person
who contributed the file and/or who is best able to provide more details
about its provenance.
CITATION: Format is "surname[[, surname] and surname], Publication
abbreviation with spaces and no periods, volume, page[-page], (year)"
COMMENT: This one is optional and is used to hold any other text that
can not go elsewhere.
If the first line of the file is always skipped by the file reader,
then the first line should begin with the DATE keyword. If the file
format supports comment lines, then the first line should be a comment
line with the metadata e.g. "# DATE: 2010-01-01..." If the first line
of the file is required to begin with data, then the metadata will be
appended to the first line e.g. "7 DATE: 2010-01-01..."
The prefix of each file indicates the element(s) it is parameterized
for. An additional lower-case identification tag may be appended.
Si = Silicon
SiC = Silicon and Carbon
Au_u3 = Gold universal 3
The suffix of each file indicates the pair style it is used with:
adp ADP angular dependent potential
airebo AI-REBO and REBO potentials
bop.table BOP potential, tabulated form
cdeam concentration-dependent EAM
comb COMB potential
comb3 COMB3 potential
eam embedded atom method (EAM) single element, DYNAMO funcfl format
eam.alloy EAM multi-element alloy, DYNAMO setfl format
eam.fs Finnis-Sinclair EAM format (single element or alloy)
edip EDIP potential for silicon-based materials
eim embedded-ion method (EIM) potential
lcbop LCBOP long-range bond-order potential
meam modified EAM (MEAM) library and individual elements/alloys
meam.spline modified EAM (MEAM) spline potential
meam.sw.spline modified EAM (MEAM) Stillinger-Weber spline potential
mesocnt mesoscopic carbon nanotube (CNT) potential
mgpt model generalized pseudopotential theory (MGPT) potential
nb3b.harmonic nonbonded 3-body harmonic potential
poly polymorphic 3-body potential
reax ReaxFF potential (see README.reax for more info)
smtbq second moment tight binding QEq (SMTBQ) potential
snap SNAP potential
snapcoeff SNAP potential
snapparam SNAP potential
streitz Coulombic portion of Streitz-Mintmire potential
sw Stillinger-Weber potential
tersoff Tersoff potential
tersoff.mod modified Tersoff potential
tersoff.zbl Tersoff with ZBL core
vashishta Vashishta 2-body and 3-body potential
435ac9078b