X-Ray photoelectron spectroscopy (XPS) and near edge X-ray absorption fine structure (NEXAFS) studies have been performed on ethyl mercaptan adsorbed on a clean Cu(111) surface at 85 K. At submonolayer coverage (0.36 ML), two different states of sulfur (thiolate) are identified with the aid of XPS investigations. Polarization dependence of S K-edge NEXAFS of the submonolayer phase indicates that the S-C bond for the two thiolate phases are tilted 33 +/- 7degrees and 30 +/- 7degrees from the surface. (C) 2003 Elsevier B.V. All rights reserved.