The disulphide group in organic compounds: conformational dependence of core and valence sulphur electronic levels by X-ray photoelectron spectroscopy

Abstract

An X-ray photoelectron spectroscopic study is reported on symmetric acyclic aliphatic disulphides and cyclic or acyclic aromatic disulphides. Core-level binding energies and sulphur lone-pair peculiarities (energy splitting, binding energy, and peak intensity) provide detailed information on the conformation of the C–S–S–C entity (C–S and S–S bond lengths, CSS/SSC dihedral angle). These relations are then applied in cases where crystallographic data are not available (di-n-butyl disulphide, di-n-hexyl disulphide, and 2,2′-dinaphthyl disulphide).