Jahn-Teller Distortion and Dissociation of CCl$_4^+$ by Transient X-ray Spectroscopy Simultaneously at the Carbon K- and Chlorine L-Edge

Andrew D. Ross; Diptarka Hait; Valeriu Scutelnic; Eric A. Haugen; Enrico Ridente; Mikias B. Balkew; Daniel M. Neumark; Martin Head-Gordon; Stephen R. Leone

doi:10.1039/d2sc02402k

arXiv · 2204.13800

Jahn-Teller Distortion and Dissociation of CCl$_4^+$ by Transient X-ray Spectroscopy Simultaneously at the Carbon K- and Chlorine L-Edge

Andrew D. Ross·Diptarka Hait·Valeriu Scutelnic·Eric A. Haugen·Enrico Ridente·Mikias B. Balkew·Daniel M. Neumark·Martin Head-Gordon·Stephen R. Leone

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Abstract

X-ray Transient Absorption Spectroscopy (XTAS) and theoretical calculations are used to study CCl$_4^+$ prepared by 800 nm strong-field ionization. XTAS simultaneously probes atoms at the carbon K-edge (280-300 eV) and chlorine L-edge (195-220 eV). Comparison of experiment to X-ray spectra computed by orbital-optimized density functional theory (OO-DFT) indicates that after ionization, CCl$_4^+$ undergoes symmetry breaking driven by Jahn-Teller distortion away from the initial tetrahedral structure (T$_d$) in 6$\pm$2 fs. The resultant symmetry-broken covalently bonded form subsequently separates to a noncovalently bound complex between CCl$_3^+$ and Cl over 90$\pm$10 fs, which is again predicted by theory. Finally, after more than 800 fs, L-edge signals for atomic Cl are observed, indicating dissociation to free CCl$_3^+$ and Cl. The results for Jahn-Teller distortion to the symmetry-broken form of CCl$_4^+$ and formation of the Cl -- CCl$_3^+$ complex characterize previously unobserved new species along the route to dissociation.

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Andrew D. Ross, Diptarka Hait, Valeriu Scutelnic, Eric A. Haugen, Enrico Ridente, Mikias B. Balkew, Daniel M. Neumark, Martin Head-Gordon, Stephen R. Leone. 2022-04-28. Jahn-Teller Distortion and Dissociation of CCl$_4^+$ by Transient X-ray Spectroscopy Simultaneously at the Carbon K- and Chlorine L-Edge. https://doi.org/10.1039/d2sc02402k

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