# # CDDL HEADER START # # The contents of this file are subject to the terms of the Common Development # and Distribution License Version 1.0 (the "License"). # # You can obtain a copy of the license at # http://www.opensource.org/licenses/CDDL-1.0. See the License for the # specific language governing permissions and limitations under the License. # # When distributing Covered Code, include this CDDL HEADER in each file and # include the License file in a prominent location with the name LICENSE.CDDL. # If applicable, add the following below this CDDL HEADER, with the fields # enclosed by brackets "[]" replaced with your own identifying information: # # Portions Copyright (c) [yyyy] [name of copyright owner]. All rights reserved. # # CDDL HEADER END # # # Copyright (c) 2012, Regents of the University of Minnesota. All rights reserved. # # Contributors: # Ryan S. Elliott # Ellad B. Tadmor # Valeriu Smirichinski # Amit Singh # Mingjian Wen This directory (Three_Body_Stillinger_Weber_Balamane_Si__MO_113686039439_003) contains Balamane et al rescaled Stillinger-Weber potential Model based on the KIM Model Driver Three_Body_Stillinger_Weber. This Model implements the Stillinger-Weber (SW) potential for Si with a rescaled value of epsilon parameter used in the SW potential. The original epsilon value was 2.1682 eV [Ref 1]. Balamane et al [Ref 2, 3] rescaled it to 2.315 eV so that experimental cohesive energy E_coh = 4.63 eV can be obtained. The original SW potential gives E_coh = 4.3364 eV. The following files are in this directory: Three_Body_Stillinger_Weber_Balamane_Si.params first line: 1 (number of species) Then the following 9 parameters: A(in ev) B p q sigma(in Angstrom) lambda(in eV) gamma(in Angstorm) costheta_0 cutoff Any additional lines will be silently ignored. LICENSE.CDDL The Common Development and Distribution License (CDDL) Version 1.0 file Makefile makefile to compile and build the Model based on the specified KIM Model Driver README This file References: 1. F. H. Stillinger and T. A. Weber, "Computer simulation of local order in condensed phases of silicon", Phys. Rev. B, vol. 31, 5262-5271, 1985 2. H. Balamane, T. Halicioglu and W. A. Tiller, "Comparative study of silicon empirical interatomic potentials", Phys. Rev. B, vol. 46, 2250-2279, 1992 3. Balamane et al., Phys. Rev. B, vol 40, 9999-10001, 1991 4. Ellad B. Tadmor and Ronald E. Miller, Modeling Materials: Continuum, Atomistic and Multiscale Techniques, Cambridge University Press, 2011 ############################################################################### The functional form of the SW potential is rewritten as: E = sum_{i,j>i} phi_2(rij) + sum_{i, j!=i, k>j} phi_3(rij, rik, theta) phi_2(rij) = Aij*(Bij(rij/sigma_ij)^(-p) - (rij/sigma_ij)^(-q)) * exp(sigma_ij/(rij - rcutij)) phi_3(rij,rik,theta) = lambda_ijk(cos[theta] - cos[theta0])^2 * exp(gamma_ij/(rij - rcutij) + gamma_ik/(rik - rcutik)) Compared to the standard SW potential, the following redefinitions have been made: A := A*epsilon lambda := lambda*epsilon gamma := gamma*sigma rcut := a*sigma