Translation factor in basis functions used in perturbed stationary state approximation and capture in H+-H(1s) collisions

Abstract

It is argued that the translation factor in the basis functions of the perturbed stationary state approximation must, in the separated atoms limit, involve v.r rather than Rr where v is the relative velocity of the nuclei, r is the position vector of the active electron, and R is the distance between the nuclei. The adoption of the incorrect translation factor leads to the appearance of spurious terms, increasing indefinitely with R, in the transition matrix elements. This has an insignificant effect on capture in slow H⁺-H(1s) collisions.