Remarks on energetic conditions for positronium formation in non-polar solids. Coupled Dipole Method application

TL;DR

This paper presents a numerical method based on the Coupled Dipole Method to calculate the energetic conditions for positronium formation in non-polar solids, considering dipole interactions and local permittivity corrections.

Contribution

It introduces a novel application of the Coupled Dipole Method for modeling positronium formation energy in non-polar media, including local permittivity corrections.

Findings

The method improves accuracy of positronium formation energy calculations.

Electromagnetic radiation from Ps formation could serve as a new spectroscopic tool.

The approach accounts for non-isotropic medium effects on e+ -- e- interactions.

Abstract

A numerical program calculating an energy of a positron or (and) an electron near the free volume in solid n-alkanes has been build. The theory of interaction of e+ or (and) e- with this non-polar media based on polarizability has been introduced. The energy of the e+ -- e- pair in the bulk was compared to that calculated when the pair forms a positronium (Ps) inside the free volume. The calculations are based on the Coupled Dipole Method and the dipole-dipole interaction energy for induced dipoles is taken into account. Furthermore, a correction of a local permittivity for the e+ -- e- interaction is calculated taking into account the non-isotropic medium between them. The method is a step toward more accurate calculations of energetic conditions during the Ps formation in matter. The possibility of emission of the excess energy of the Ps formation as electromagnetic radiation is discussed. It is argued that if this radiation is observed, it can be used as a new spectroscopic tool providing information about microscopic properties of media.