AVS 52nd International Symposium
    Surface Science Thursday Sessions
       Session SS2-ThA

Paper SS2-ThA6
Extracting the Vibrational Ground State Reactivity of Methane on Ni(111) from Ensemble Averaged Experiments

Thursday, November 3, 2005, 3:40 pm, Room 203

Session: Gas-Surface Reaction Dynamics
Presenter: D.R. Killelea, Tufts University
Authors: D.R. Killelea, Tufts University
V. Campbell, Tufts University
A.L. Utz, Tufts University
Correspondent: Click to Email
Beam-surface studies have uncovered key details of the dynamics of methane dissociation on transition metal surfaces. When the measured reactivity is averaged over the population distribution of vibrational states in the beam, the data may obscure the role of individual vibrational states in promoting reaction. Here, we measure the reactivity of CH@sub 4@ beams impinging on a Ni(111) surface. We vary the vibrational energy of the beams by changing the beam source temperature. We model the nozzle temperature effect for these data, and extrapolate to find the reactivity of CH@sub 4@ in its vibrational ground state (v=0). Our model predicts that at the low translational energies typical of thermal samples, vibrationally excited molecules account for the majority of observed reactivity.