# DATE: 2015-10-14 CONTRIBUTOR: Aidan Thompson, athomps@sandia.gov CITATION: P. Vashishta, R. K. Kalia, J. P. Rino, and I. Ebbsjo, Phys. Rev. B 41, 12197 (1990). # # Vashishta potential file for SiO2, P. Vashishta, R. K. Kalia, J. P. Rino, and I. Ebbsjo, # Phys. Rev. B 41, 12197 (1990). # # These parameters, some inferred indirectly, give a good # match to the energy-volume curve for alpha-quartz in Fig. 2 of the paper. # # These entries are in LAMMPS "metal" units: # H = eV*Angstroms^eta; Zi, Zj = |e| (e = electronic charge); # lambda1, lambda4, rc, r0, gamma = Angstroms; # D = eV*Angstroms^4; W = eV*Angstroms^6; B = eV; # other quantities are unitless # # element1 element2 element3 # H eta Zi Zj lambda1 D lambda4 # W rc B gamma r0 C cos(theta) C C C 471.74538 7 -1.201 -1.201 5.0 0.0 3.0 0.0 7.35 1.0 0.0 0.0 0.0 0.0 Si Si Si 23.67291 7 1.201 1.201 5.0 2.1636 3.00 0.0 7.35 1.0 0.0 0.0 0.0 0.0 C Si Si 447.09026 9 -1.201 1.201 5.0 1.0818 3.0 61.4694 7.35 9.003 1.0 2.90 5.0 -0.33333333 Si C C 447.09026 9 1.201 -1.201 5.0 1.0818 3.0 61.4694 7.35 9.003 1.0 2.90 5.0 -0.3333333 Si C Si 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 Si Si C 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 C Si C 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 C C Si 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0 0.0