Regge resonances in low-energy electron elastic cross sections for Ge, Sn and Pb atoms: manifestations of stable excited anions

TL;DR

This study uses Regge-pole methodology with a Thomas-Fermi potential to analyze low-energy electron collisions with Ge, Sn, and Pb atoms, revealing stable excited anions and matching experimental binding energies for Ge and Sn.

Contribution

It introduces a Regge-pole approach with core-polarization effects to predict stable excited anions in electron-atom collisions, aligning well with experimental data for Ge and Sn.

Findings

Stable excited Ge- and Sn- anions confirmed by Regge resonances

Calculated binding energies agree with experimental values for Ge and Sn

Prediction for Pb- requires experimental validation

Abstract

Low-energy E < 2 eV electron elastic collisions with Ge, Sn and Pb atoms yield stable excited Ge-, Sn- and Pb- anions. The recent Regge-pole methodology is used with Thomas-Fermi type potential incorporating the crucial core-polarization interaction to calculate elastic total and Mulholland partial cross sections. For excited Ge- and Sn- anions the extracted binding energies from the unique characteristic sharp Regge resonances manifesting stable excited states formed during the collisions agree excellently with experimental values; for Pb- the prediction requires experimental verification. The calculated differential cross sections also yield the binding energies.