Decay of highly excited atom states in their actual surroundings

Abstract

Highly excited atom states carrying single or multiple vacancies in inner and/or outer shells still represent a subject of great relevance for both basic and applied research. Particularly, for inferring ionization cross sections or elemental abundances from measured X-ray line intensities, precise knowledge of the X-ray fluorescence yields appears indispensable. Based on previous exemplifying multi-centre calculations, the present paper attempts to include environmental and multiple-vacancy aspects in a dense approximate single-centre model for third-row main-group emitter atoms, which can readily deliver realistic transfer probabilities and fluorescence yields as parameters describing the cascading de-excitation of multiply ionized atoms in their chemical surroundings. In particular, the results of the present analysis justify in retrospect the tentative use of single-hole standard fluorescence yields in recent experimental work.