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arXiv · 2312.03449

Extracting vibrational anharmonicities from short driven molecular dynamics trajectories

Pascal Parneix·Romain Maupin·Loïse Attal·Florent Calvo·Cyril Falvo
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Abstract

Anharmonicities provide a wealth of information about the vibrational dynamics, mode coupling and energy transfer within a polyatomic system. In this contribution we show how driven molecular dynamics trajectories can be used to extract anharmonicity properties under very short times of a few hundreds of vibrational periods, using two exciting fields at- and slightly off-resonance. Detailed analyses on generic quartic potential energy surfaces and applications to various model systems are presented, giving good agreement with perturbation theory. Application to a realistic molecule, cubane (C$_8$H$_8$), modeled with a tight-binding quantum force field, further indicates how the method can be applied in practical cases.

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Pascal Parneix, Romain Maupin, Loïse Attal, Florent Calvo, Cyril Falvo. 2023-12-06. Extracting vibrational anharmonicities from short driven molecular dynamics trajectories. https://doi.org/10.1007/s00214-021-02740-1

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