Dissociative grazing scattering of H-2(+) on metal surfaces: Analysis of the high-energy parts of the spectra of the scattered molecule constituents

In the present work we calculated the high energy tails of the energy distr ibutions for hydrogen molecule constituents scattered from metal surfaces a t grazing incidence of H-2(+), supposing the dissociative capture process t o contribute mainly to H-2(+). No effect of the straggling on the high ener gy tails formation was considered. The harmonic oscillator approximation wa s employed for the calculation of the centre-of-mass distributions of the k inetic energy released in the dissociation process, "vibrational temperatur e" being the only free parameter of the theory. The comparison of the calcu lations with the experimental high-energy tails of the H spectra from the s cattering of H-2(+) off Pt and Ag shows good agreement. The calculations yi eld information on the vibrational excitation of the molecules during the s cattering process. (C) 2000 Elsevier Science B.V. All rights reserved.