Dynamics of recombinative desorption: Angular distributions of H2, HD, and D2 desorbing from Cu(111)

Abstract

We have determined the angular distributions of H₂, HD, and D₂ desorbing from Cu(111) for surface temperatures in the range 370–800 K. These are found to be strongly peaked and symmetric about the surface normal in every case. Results for all three isotopes are found to be indistinguishable, being close to a cos ¹²θ_f distribution at 600 K, slightly narrower at 370 K, and slightly broader at 800 K. Results are discussed in terms of other previous desorption measurements and related to adsorption data via detailed balance.