Comparative study of C-H stretch and bend vibrations in methane activation on Ni(100) and Ni(111).
State-resolved measurements on clean Ni(100) and Ni(111) surfaces quantify the reactivity of CH4 excited to v = 3 of the nu4 bend vibration. A comparison with prior data reveals that 3nu4 is significantly less effective than the nu3 C-H stretch at promoting dissociative chemisorption, even though 3nu4 contains 30% more energy. These results contradict statistical theories of gas-surface reactivity, provide clear evidence for vibrational mode specificity in a gas-surface reaction, and point to a central role for C-H stretching motion along the reaction path to dissociative chemisorption.
Juurlink
L B F
LB
Leiden Institute of Chemistry, Gorlaeus Laboratories, Leiden University, 2300 RA Leiden, The Netherlands.
Smith
R R
RR
Killelea
D R
DR
Utz
A L
AL
D002244:Carbon / Q000032:analysis / Q000737:chemistry*; D003198:Computer Simulation; D006860:Hydrogen Bonding; D008697:Methane / Q000032:analysis / Q000737:chemistry*; D008956:Models, Chemical; D008968:Molecular Conformation; D009532:Nickel / Q000032:analysis / Q000737:chemistry*; D014732:Vibration
D002244:Carbon; D009532:Nickel; D008697:Methane