title: Vibrationally bond-selected chemisorption of methane isotopologues on Pt(111) studied by reflection absorption infrared spectroscopy.
abstract: Reflection absorption infrared spectroscopy (RAIRS) was used to probe for vibrational bond-selectivity in the dissociative chemisorption of three partially deuterated methane isotopologues on a Pt(111) surface. While a combination of incident translational energy and thermal vibrational excitation produces a nearly statistical distribution of C-H and C-D bond cleavage products, we observe that laser excitation of an infrared active C-H stretch normal mode leads to highly selective dissociation of a C-H bond for CHD3, CH2D2, and CH3D. Our results show that vibrational energy redistribution between C-H and C-D stretch modes due to methane/surface interactions is negligible during the sub-picosecond collision time which indicates that vibrational bond-selectivity may be the rule rather than the exception in heterogeneous reactions of small polyatomic molecules.
authors.affiliation: Laboratoire de Chimie Physique Moléculaire, Ecole Polytechnique Fédérale de Lausanne, Switzerland.
authors.forename: Li
authors.initials: L
authors.lastname: Chen
authors.forename: Hirokazu
authors.initials: H
authors.lastname: Ueta
authors.forename: Régis
authors.initials: R
authors.lastname: Bisson
authors.forename: Rainer D
authors.initials: RD
authors.lastname: Beck