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arXiv · 1608.08768

Surface hopping methodology in laser-driven molecular dynamics

T. Fiedlschuster·J. Handt·E. K. U. Gross·R. Schmidt
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Abstract

A theoretical justification of the empirical surface hopping method for the laser-driven molecular dynamics is given utilizing the formalism of the exact factorization of the molecular wavefunction [Abedi et al., PRL $\textbf{105}$, 123002 (2010)] in its quantum-classical limit. Employing an exactly solvable $\textrm H_2^{\;+}$-like model system, it is shown that the deterministic classical nuclear motion on a single time-dependent surface in this approach describes the same physics as stochastic (hopping-induced) motion on several surfaces, provided Floquet surfaces are applied. Both quantum-classical methods do describe reasonably well the exact nuclear wavepacket dynamics for extremely different dissociation scenarios. Hopping schemes using Born-Oppenheimer surfaces or instantaneous Born-Oppenheimer surfaces fail completely.

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T. Fiedlschuster, J. Handt, E. K. U. Gross, R. Schmidt. 2016-08-31. Surface hopping methodology in laser-driven molecular dynamics. https://doi.org/10.1103/physreva.95.063424

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