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arXiv · 2509.09345

Attochemical control of nuclear motion despite fast electronic decoherence

Lina Fransén·Sandra Gomez·Morgane Vacher
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Abstract

Short-in-time, broad-in-energy attosecond or few-femtosecond pulses can excite coherent superpositions of several electronic states in molecules. This results in ultrafast charge oscillations known as charge migration. A key open question in the emerging field of attochemistry is whether these electron dynamics, which due to decoherence often last only for a few femtoseconds, can influence longer-time scale nuclear rearrangements. Herein, we address this question through full-dimensional quantum dynamics simulations of the coupled electron-nuclear dynamics initiated by ionization and coherent excitation of ethylene. The simulations of this prototype organic chromophore predict electronic coherences with half-lives of less than 1 fs. Despite their brevity, these electronic coherences induce vibrational coherences along the derivative coupling vectors that persist for at least 50 fs. These results suggest that short-lived electronic coherences can impart long-lasting legacies on nuclear motion, a finding of potential importance to the interpretation of attosecond experiments and the development of strategies for attochemical control.

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Lina Fransén, Sandra Gomez, Morgane Vacher. 2025-09-11. Attochemical control of nuclear motion despite fast electronic decoherence. https://arxiv.org/abs/2509.09345

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