Least-squares variational treatment of positron (electron)–diatomic molecule scattering

Abstract

A computer code based on the least-squares variational method (LSVM) is developed for the treatment of the collisions of positrons and electrons with diatomic molecules. The code was tested and employed for the investigation of the elastic scattering of positrons and electrons by hydrogen molecules within the framework of the adiabatic approximation. The system is described by a set of prolate spheroidal coordinates which is the most suitable representation of diatomic molecules. Reliable convergence of the scattering phaseshifts has been achieved by optimizing the nonlinear parameters and increasing the number of L2 components of the trial wavefunctions. The cross section of the lowest partial wave is calculated at energies varying from 0.136 eV to 13.6 eV, under the assumption that positronium formation, exchange interactions, and all excitation channels are closed. A comparison is presented between our results and those determined by other authors.

An analytical treatment of the energy spectrum of hydrogen-like atoms perturbed by a generalized van der Waals potential

“…(2)). Figs (6,7,8) show that He ion does not change with β because it is one of the noble gases, the most stable atomic systems. In Figs.…”

Variational calculation of low-energy positron life time in Xe atoms

“…It was applied to obtain the wave function of the continuum Auger electron emitted from an ionized Ne atom [20] and developed to study positron-H molecules scattering [21]. Good results were obtained in the former calculations.…”