Scattering of hyperthermal nitrogen atoms from the Ag(111) surface.

J Phys Chem A

FOM Institute for Plasma Physics Rijnhuizen, Euratom FOM Association, P.O. Box 1207, 3430 BE Nieuwegein, The Netherlands.

Published: December 2009

Measurements on scattering of hyperthermal N atoms from the Ag(111) surface at temperatures of 500, 600, and 730 K are presented. The scattered atoms have a two-component angular distribution. One of the N components is very broad. In contrast, scattered Ar atoms exhibit only a sharp, single-component angular distribution. There are noteworthy features in the angle-resolved energy of the scattered N when compared with Ar. Taking into account the relative masses involved, N atoms lose significantly more energy at the surface than Ar. However, there is a preferential loss mechanism that predominantly affects low-energy N atoms with small total scattering angle trajectories. The results are interpreted in terms of probing of different interaction potentials: strongly attractive and almost purely repulsive, and spin-state changes during the interaction of N with the surface appear probable.

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http://dx.doi.org/10.1021/jp905167pDOI Listing

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