Collision-Induced Vibrational Excitation and Dissociation of Hydrogen with Alkali Atoms and Ions from 2 to 50 eV

Abstract

Inelastic energy losses for Na0, Na+, K0, and K+ backscattered from H2 and D2 have been measured. At center-of-mass energies below15 ∼ eV for Na and ∼ 20 eV for K, the collisions yield vibrational excitations which are compared with the one-dimensional exact classical calculations of Secrest. The vibrational excitation in the Na+–H2 and Na0–H2 system is in excellent agreement with three-dimensional classical calculations of Cheng and Wolfsberg. Above these energies the molecules are dissociated but the energy loss distribution of the alkali projectile remains sharp and in the case of Na–H approaches the maximum loss possible at 50 eV.