A DFT study on the adsorption of methoxy on the Rh (111) surface

The interaction of methoxy (CH₃O·) with Rh (111) surface was studied by hybrid-method B3LYP based on density functional theory. The Lanl2dz basis set for Rh atom and the 6-31G(d,p) basis set for O, C and H atoms were used. The Rh13(9,4) cluster was used to simulate the surface. Four typical adsorption sites, top, hcp, bridge and fcc sites, were investigated theoretically and the information about the preferred adsorption geometry and energy of CH₃O· species was extracted. The results show that the bridge site is more favorable than the other adsorption sites and the amount of electronic charge transferred from Rh to methoxy species is higher than those on the other sites when CH₃O· is bonded to the surface via the oxygen atom. C—O bond is activated and its stretching frequency is red shifted in the process of C—O bond adsorption on Rh (111) surface.