DFT studies on the phenol and thiophenol interaction on an undecagold cluster surface

The interaction of Au11 clustered phenol or thiophenol was carried out by density functional theory (DFT), the results showing that the O-H or S-H bonds were activated on the Au-catalytic surface by their strong absorption. For phenol, OH bonded with Au11 while for thiophenol both benzene and sulfur interacted with Au11, suggesting that the S-H bond cleavage on thiophenol is easier than O-H on phenol; this is supported by their binding energies and the molecular orbital studies, which indicate that the phenol adsorption on the Au-surface is an orbital controlled reaction while for thiophenol both charge density transfer and orbital are involved. In addition, the spectra of the density of state ( DOS) confirm that there is a mixing of the p orbitals (O or S) of phenol or thiophenol with the d orbitals of Au to form an adsorption bond. (C) 2008 Elsevier B.V. All rights reserved.