Transferable nonorthogonal tight-binding parameters for silicon

Abstract

Nonorthogonal Slater-Koster (‘‘tight-binding’’) parameters have been fitted to linear muffin-tin orbital band structures of silicon in the hypothetical sc, fcc, and bcc structures at the density of ordinary diamond-cubic silicon. First- and second-neighbor parameters are used for all three structures. When the eight parameters ($H_{\mathrm{ss}\sigma }$,...,$S_{\mathrm{pp}\pi }$) are plotted as a function of neighbor distance, they describe approximate smooth curves which align well with the values found by Mattheiss and Patel for diamond-cubic Si, even though local coordination is entirely different. This suggests an approximate transferability of tight-binding parameters, at least if the volume is constant and coordination number is four or higher.