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arXiv · 2208.13539

Coupling of distant parts of pyrrole molecule through virtual and resonant states

Ragesh Kumar T P·P. Nag·M. Ranković·T. F. M. Luxford·Kočišek·Z. Mašín·J. Fedor
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Abstract

We experimentally show that the N-H bond cleavage in pyrrole molecule following resonant electron attachment is allowed and controlled by the motion of the atoms which are not dissociating, namely of the carbon-attached hydrogen atoms. In order to interpret these findings, we have developed a method for locating all resonant and virtual states of an electron-molecule system in the complex plane, based on all-electron R-matrix scattering calculations. Mapping these as a function of molecular geometry allows us to separate two contributing dissociation mechanisms: a $π^*$ resonance formation inducing strong bending deformations and a non-resonant $σ^*$ mechanism originating in a virtual state. The coupling between the two mechanisms is enabled by the out-of-plane motion of the C-H bonds and we show it must happen on an ultrafast few-fs timescale.

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Ragesh Kumar T P, P. Nag, M. Ranković, T. F. M. Luxford, Kočišek, Z. Mašín, J. Fedor. 2022-08-29. Coupling of distant parts of pyrrole molecule through virtual and resonant states. https://arxiv.org/abs/2208.13539

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