Eigenstate-resolved studies of gas-surface reactivity:: CH4 (ν3) dissociation on Ni(100)

A new experimental technique uses state-resolved infrared laser excitation to probe a polyatomic molecule's dissociative chemisorption dynamics with previously unattainable detail. Methane molecules excited to v = 1 of the v(3) C-W stretching vibration are up to 1600 times more reactive on a clean Ni(100) surface than are molecules in the ground vibrational state. Over a translational energy range of 27 to 54 kJ/mol, their absolute reaction probability increases from 3 x 10(-1) to 6 x 10(-3), which indicates that v(3) is responsible only in part for the vibrational activation reported in previous studies.