Ionic-covalent collision interactions

Abstract

Several classes of collision problems are mediated by interactions between ionic and covalent potential energy curves. Two prominent cases are ion-ion recombination, A+ + B− A + B, and electron capture in multiply charged ion, atom collisions, Aq+ + B A(q – 1)+ + B+. Professor Bates and his students provided the theoretical framework upon which many successful theories are based for the above reactions. Advances in computational methods have allowed the calculation of cross sections with accuracy unrealizable only a decade ago. Important physical effects, such as electron translation factors that were pointed out by Bates and McCarroll in 1958, are routinely incorporated in present calculations. Pseudopotential and model-potential molecular structure methods now provide the input of accurate eigenenergies and eigenfunctions for the scattering calculations. However, important problems are still unsolved. One of these problems is the molecular and collisional description of discrete states embedded in a continuum as it arises in collisions of highly charged, multiply charged ions with many electron atomic targets.