NEXAFS study of 1-butanethiol adsorbed on Cu(111) and square root of 7 x square root of 7 R19.1 degrees S/Cu(111)

The adsorption of 1-butanethiol on Cu(111) and square root of 7 x square root of 7 R19.1 degrees S/Cu(111) surfaces has been studied by S K-edge near edge X-ray absorption fine structure (NEXAFS) spectroscopy and thermal desorption spectroscopy. Upon adsorption on clean Cu(111) surface at room temperature, butanethiolate as well as atomic sulfur is formed. For the butanethiolate, the S-C bond is found predominately perpendicular to the surface as revealed by polarization analysis. In contrast, on square root of 7 x square root of 7 R19.1 degrees S/Cu(111) surface, the S-H and S-C bonds of the butanethiol stay intact, resulting in a weakly chemisorbed butanethiol.