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Soviet Journal of Low Temperature Physics

Features of the self-trapping of highly excited states in neon and argon crystals at low temperature

A. G. Belov, E. M. Yurtaeva, V. N. Svishchev

Published Mar 1, 1981• 2 citations
Publisher

Abstract

We have examined the luminescence from highly excited self-trapped one-center states, the relaxation processes of the band excitations, and the mechanisms of formation of highly excited quasiatomic centers in low-temperature crystals of the light rare gases and their solid solutions. The fundamental channel of population of highly excited emitting centers involves hole self-trapping with formation of two-center R2+ states; dissociative recombination of these forms one-center np5(n + 1)p excitations. We discuss the effect of self-trapping of highly excited states on the population of the lowest emitting centers in neon and argon crystals.

DOI
10.1063/10.0030486

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We have examined the luminescence from highly excited self-trapped one-center states, the relaxation processes of the band excitations, and the mechanisms of formation of highly excited quasiatomic centers in low-temperature crystals of the light rare gases and their solid solutions. The fundamental channel of population of highly excited emitting centers involves hole self-trapping with formation of two-center R2+ states; dissociative recombination of these forms one-center np5(n + 1)p excitations. We discuss the effect of self-trapping of highly excited states on the population of the lowest emitting centers in neon and argon crystals.
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Abstract It is shown that in the process of the exciton two‐center self‐trapping the resonance bonds generating a free exciton state are redistributed so that the total resonance contribution to the energy increases. 50% of the electronic excitation is concentrated inside a two‐center quasimolecule close to the self‐trapping threshold. The rest is distributed in neighbouring atoms, resulting in a generation of weaker extrinsic bonds along with the intermolecular resonance one. The attendant deformation of the molecular term produces a decrease in the self‐trapping barrier and an appreciable increase in its transparency.
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