X-ray-photoelectron-spectroscopy determination of the valence band structure of polymeric sulfur nitride, (sn)x

We report x-ray photoemission (XPS) measurements on polymeric sulfur nitride, (SN)x. Both valence-band states and core-level binding energies have been studied. The charge transfer in the S+N bond is estimated to be 0.30-0.42 electrons. The XPS spectra are compared with densities of states derived from a single-chain tight-binding calculation and also with three-dimensional orthogonal-plane-wave (OPW) calculations based on the two reported (SN)x crystal structures. Good quantitative agreement is found with the OPW density of states. © 1975 The American Physical Society.