On photoionization of the subvalent subshells of noble gas endohedral atoms

TL;DR

This paper investigates the complex interference effects in the photoionization of noble gas endohedral atoms, revealing how neighboring shells, fullerene reflection, and resonance effects influence the ionization cross-section.

Contribution

It introduces a theoretical framework that accounts for multiple interference factors affecting photoionization in NG@F atoms, extending understanding of endohedral atom behavior.

Findings

Identification of strong interference patterns in photoionization cross-sections.

Development of a model incorporating shell polarization and electron reflection effects.

Application to Ne, Ar, Kr, and Xe atoms showing the model's effectiveness.

Abstract

We demonstrate strong interference patterns in the photoionization cross-section of the subvalent subshells of noble gas (NG) endohedral atoms NG@F. This interference is a result of common action of three factors: the effect of neighboring atomic subshells, reflection of photoelectron waves by the fullerene F shell and resonance modification of the incoming photon beam by the complex effect under the action of the F electrons. We have considered the outer ns-subshells for Ne, Ar, Kr and Xe noble gas atoms. The polarization of the fullerene shell is expressed via the F total photoabsorption cross section. The photoelectron reflection from the static F potential is taken into account in the frame of the so-called bubble potential that is a spherical zero--thickness type potential. It is assumed in the derivations that NG is centrally located in the fullerene. It is assumed also, in accordance with the available experimental data, that the fullerene radius is much bigger than the atomic radius and the thickness of the fullerene shell. These assumptions permit, as demonstrated recently, the NG@F photoionization cross section to be presented as a product of the NG subvalent cross section and two calculated factors that account for polarization of the F electron shell and reflection of photoelectrons by the fullerene static potential.