Localization of Inner-Shell Photoelectron Emission and Interatomic Coulombic Decay in Ne$_2$

TL;DR

This study investigates how inner-shell photoelectrons and interatomic Coulombic decay occur in Ne₂ molecules, revealing localized emission processes through experimental measurements and theoretical calculations.

Contribution

It provides the first detailed experimental and theoretical analysis of localized inner-shell photoelectron emission and ICD in Ne₂ molecules.

Findings

Localized emission of photoelectrons and ICD electrons observed

Asymmetric angular distributions indicate site-specific decay

Experimental results supported by Hartree-Fock calculations

Abstract

We used Cold Target Recoil Ion Momentum Spectroscopy (COLTRIMS) to investigate the decay of Ne$_2$ after K-shell photoionization. The breakup into Ne$^{1+}$ / Ne$^{2+}$ shows interatomic Coulombic decay (ICD) occurring after a preceding atomic Auger decay. The molecular frame angular distributions of the photoelectron and the ICD electron show distinct, asymmetric features, which imply localization of the K-vacancy created at one of the two atomic sites of the Ne$_2$ and an emission of the ICD electron from a localized site. The experimental results are supported by calculations in frozen core Hartree-Fock approach.