Non-ergodic dissociative valence double ionization of SF6

TL;DR

This study investigates the double ionization of SF6 and finds that energy redistribution is incomplete, indicating non-ergodic behavior in dissociation.

Contribution

The paper reveals that doubly charged SF6 ions exhibit non-ergodic behavior, challenging assumptions about energy distribution in molecular dissociation.

Findings

Energy redistribution is incomplete in SF6^2+ dissociation.

Molecular size required for ergodic behavior is larger for doubly charged ions.

Experimental results differ from statistical model predictions.

Abstract

The dissociative double ionization of sulphur hexafluoride, SF6, in the ionization energy range from threshold up to 48.4 eV has been examined in detail using a multiple coincidence electron-ion technique. The results are interpreted by comparison with molecular dynamics simulations, high level molecular structure calculations and with a statistical model of the ion breakdown. Comparison between the experimental breakdown pattern and the pattern derived on the basis of statistical theory indicates that the energy redistribution required for fully statistical behaviour is incomplete on the timescale of the dissociation reactions of \documentclass[12pt]{minimal}
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\begin{document}$${\text{SF}}_6^{2 + }$$\end{document}, suggesting that the molecular size at which ergodic behaviour becomes dominant is larger for doubly and multiply charged ions than for neutral and singly ionized molecules.

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