The band structure and optical properties of sulphur nitride polymer. I. Band structure

Abstract

A non-empirical calculation of the energy band structure of (SN)x has been made on a tight-binding model using the crystal structure by Boudeulle (1975). An important feature is the appearance of two overlapping conduction bands for an isolated chain, which allows (SN)x to have metallic character at all temperatures. It has been shown that the most important factor in determining the band structure near the Fermi level is the degree of s-p mixing. The three-dimensional band structure is then obtained using simple perturbation theory. Finally, assignments are proposed for features in the absorption spectrum in the energy range 0.5 eV to 20 eV.