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#
# KIM-API: An API for interatomic models
# Copyright (c) 2013--2022, Regents of the University of Minnesota.
# All rights reserved.
#
# Contributors:
#    Ryan S. Elliott
#    Andrew Akerson
#
# SPDX-License-Identifier: LGPL-2.1-or-later
#
# This library is free software; you can redistribute it and/or
# modify it under the terms of the GNU Lesser General Public
# License as published by the Free Software Foundation; either
# version 2.1 of the License, or (at your option) any later version.
#
# This library is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
# Lesser General Public License for more details.
#
# You should have received a copy of the GNU Lesser General Public License
# along with this library; if not, write to the Free Software Foundation,
# Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
#


This directory (LennardJones612__MD_414112407348_003) contains a Lennard-Jones
Driver which reads a parameter file containing the parameters for up to 139
species.  It supports shifted and non-shifted energy behavior.  The driver is
written in C++.  This Model Driver expects one parameter file as decribed
below.

The model driver implements the functional form:

       phi_{ij}(r) = 4 * epsilon_{ij} *
                     [ (sigma_{ij}/r)^12 - (sigma_{ij}/r)^6 ] + shift_{ij},

where i, j = 0, 1, 2, ..., N-1, and N is the number of supported species.


The format of the parameter file is as follows:

* Blank lines and lines beginning with the `#' character are ignored.

* Line 0 : N, shift
   - N         : integer number of distinct particle species
   - shift     : integer value: 0-for no shift; 1-for shifts.
                 All shift values are computed at run time
* Lines 1,2,...: species_i, species_j, cutoff, epsilon, sigma
   - species_i : A valid KIM API particle species string
   - species_j : A valid KIM API particle species string
   - cutoff    : double cutoff distance value (in Angstroms) for phi_{ij}(r)
   - epsilon   : double energy value (in eV) for  epsilon_{ij}
   - sigma     : double sigma distance value (in Angstroms) for sigma_{ij}


The parameter file must contain all "like-like" parameter sets (i.e., lines
where species_i and species_j are identical) for each species which occurs in
the file.  The model driver uses the Lorentz-Berthelot rules to generate any
"cross-interaction" parameter sets which are not provided.  The model driver
sets the `influcenceDistance' argument to max_{ij}(cutoff_{ij}).  The model
driver uses this same influenceDistance as its NeighborListCutoff value.