Adsorption of benzene on platinum black. A neutron scattering study

Abstract

Incoherent inelastic neutron scattering spectra (0–1000 cm^–1) of benzene adsorbed on platinum black (0.1 ⩽θ⩽ 2.0) are reported. The spectra, which vary markedly with coverage, indicate that the plane of the C₆H₆ molecule is lying parallel to the metal surface. Shifts in the low-wavenumber intramolecular modes also indicate that the interaction of C₆H₆ is stronger with platinum than with nickel. Some of the vibrations of adsorbed C₆H₆ relative to the substrate have been assigned, e.g. at θ= 0.75 the Pt—C₆H₆ stretching and tilting modes occur at 522 and 638 cm^–1, respectively.