Nonorthogonal tight-binding molecular-dynamics scheme for silicon with improved transferability

Department of Physics and Astronomy, University of Kentucky, Lexington, Kentucky 40506~Received 9 September 1996!A previously proposed @Phys. Rev. B 50, 11 577 ~1994!# generalized tight-binding theory for silicon incor-porating explicit use of nonorthogonality of the basis is modified to improve transferability. Better agreementis obtained over the original scheme for bond lengths, high-pressure bulk phases, and vibrational frequencies.@S0163-1829~97!03716-8#I. INTRODUCTION