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arXiv · 1711.00646

Quasi-classical approaches to vibronic spectra revisited

Sven Karsten·Sergei D. Ivanov·Sergey I. Bokarev·Oliver Kühn
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Abstract

The framework to approach quasi-classical dynamics in the electronic ground state is well established and is based on the Kubo-transformed time correlation function (TCF), being the most classical-like quantum TCF. Here we discuss whether the choice of the Kubo-transformed TCF as a starting point for simulating vibronic spectra is as unambiguous as it is for vibrational ones. A generalized quantum TCF is proposed that contains many of the well-established TCFs as particular cases. It provides a framework to develop numerical protocols for simulating vibronic spectra via quasi-classical trajectory-based methods that allow for dynamics on many potential energy surfaces and nuclear quantum effects. The performance of the methods based on the well-known TCFs is investigated on 1D anharmonic model systems at finite temperatures. The flexibility inherent to the formulation of the generalized TCF provides a route to construct new TCFs that may lead to better numerical protocols as is shown on the same models.

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Sven Karsten, Sergei D. Ivanov, Sergey I. Bokarev, Oliver Kühn. 2017-11-02. Quasi-classical approaches to vibronic spectra revisited. https://doi.org/10.1063/1.5011764

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