Quantum-Mechanical Transition Probabilities for Atom–Atomic-Oscillator Collisions with Morse Potential Interaction

Abstract

Exact quantum-mechanical transition probabilities for the collision of an atom with an atomic oscillator for the case in which the interaction has the form of a Morse potential are obtained by numerical integration of the relevant close-coupled scattering equations. These transition probabilities are compared with approximate ones calculated from distorted-wave theory over a range of parameters which have been of interest in examining the collision of helium atoms with a tungsten surface. Some information is obtained concerning the range of validity of the first-order theory, and certain suggestions that have appeared in the literature for correcting the distorted-wave results are found to be inadequate.

Semiclassical Transition Probabilities for Atom—Atomic-Oscillator Collisions with Morse Potential Interaction

“…1. Z is the separation of incident atom A from oscillator atom B measured from the minimum in the Morse potential, Zoo The potential is (1) in which E is the well depth and L is the usual parameter associated with the steepness of the potentiaL Heidrich, Wilson, and R app6 have shown that for a Morse potential between an atom and a harmonic oscillator the average energy transferred on collision, in which there is (2) in which tJ> = tan-ie (E/ Eo)1/2J, a and m are dimensionless parameters and …”