Coverage effects and the nature of the metal-sulfur bond in S/Au(111): high-resolution photoemission and density-functional studies.

摘要: The bonding of sulfur to surfaces gold is an important subject in several areas chemistry, physics, and materials science. Synchrotron-based high-resolution photoemission first-principles density-functional (DF) slab calculations were used study the interaction with a well-defined Au(111) surface polycrystalline gold. Our experimental theoretical results show complex behavior for sulfur/Au(111) interface as function coverage temperature. At small coverages, adsorption S on fcc hollow sites substrate energetically more favorable than bridge or a-top sites. Under these conditions, behaves weak electron acceptor but substantially reduces density-of-states that exhibits near Fermi edge. As increases, there weakening Au−S bonds (with simultaneous reduction Au → charge transfer modification sp hybridization) facilitates changes ...