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arXiv · 1609.00644

An analysis of nonadiabatic ring-polymer molecular dynamics and its application to vibronic spectra

Jeremy O. Richardson·Philipp Meyer·Marc-Oliver Pleinert·Michael Thoss
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Abstract

Nonadiabatic ring-polymer molecular dynamics employs the mapping approach to describe nonadiabatic effects within the ring-polymer ansatz. In this paper, it is generalized to allow for the nuclear and electronic degrees of freedom to be described by different numbers of ring-polymer beads. Analysis of the resulting method shows that as the number of electronic mapping variables increases, certain problems associated with the approach are removed, such as the non-unique choice of the mapping Hamiltonian and negative populations leading to inverted potential-energy surfaces. Explicit integration over cyclic variables reduces the sign problem for the initial distribution in the general case. A new application for the simulation of vibronic spectra is described and promising results are presented for a model system.

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Jeremy O. Richardson, Philipp Meyer, Marc-Oliver Pleinert, Michael Thoss. 2016-09-02. An analysis of nonadiabatic ring-polymer molecular dynamics and its application to vibronic spectra. https://doi.org/10.1016/j.chemphys.2016.09.036

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