A study of the electronic structures of SN, S2N2, S4N4, NO, and N2O2 and their implications for (SN)x

Abstract

SCF–Xα–SW calculations have been carried out for SN, S2N2, and S4N4 as well as the analogous oxides NO and N2O2. The electronic charge distribution of the sulfides is remarkably uniform leading to highly polar SN bonds (∼S+1/2N−1/2) in contrast to the oxides where the NO bonds involve less charge transfer and in the opposite direction. The inclusion of d functions on sulfur is shown to have only minor effects on the electronic structure of the sulfides. Contour plots of several of the molecular orbitals are presented. The importance of the polar bonds in S2N2 in determining the structure of metallic polymeric sulfur nitride (SN)x is discussed. Predictions are made on the likelihood of forming (SN)x analogs with a different Group V or Group VI element.