Communication: Angle-resolved thermal dissociative sticking of CH4 on Pt(111): Further indication that rotation is a spectator to the gas-surface reaction dynamics

Effusive molecular beam measurements of angle-resolved thermal dissociative sticking coefficients for CH4 impinging on a Pt(111) surface, at a temperature of 700 K, are reported and compared to theoretical predictions. The reactivity falls off steeply as the molecular angle of incidence increases away from the surface normal. Successful modeling of the thermal dissociative sticking behavior, consistent with existent CH4 supersonic molecular beam experiments involving rotationally cold molecules, required that rotation be treated as a spectator degree of freedom. (C) 2012 American Institute of Physics. [doi:10.1063/1.3685833]