Ring-polymer instanton theory of electron transfer in the nonadiabatic limit

Jeremy O. Richardson

doi:10.1063/1.4932362

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arXiv · 1508.05195

Ring-polymer instanton theory of electron transfer in the nonadiabatic limit

Jeremy O. Richardson

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Abstract

We take the golden-rule instanton method derived in the previous paper [arXiv:1509.04919] and reformulate it using a ring-polymer approach. This gives equations which can be used to compute the rates of electron-transfer reactions in the nonadiabatic (golden-rule) limit numerically within a semiclassical approximation. The multidimensional ring-polymer instanton trajectories are obtained efficiently by minimization of the action. In this form, comparison with Wolynes' quantum instanton method [P. G. Wolynes, J. Chem. Phys. 87, 6559 (1987)] is possible and we show that our semiclassical approach is the steepest-descent limit of this method. We discuss advantages and disadvantages of both methods and give examples of where the new approach is more accurate.

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Jeremy O. Richardson. 2015-08-21. Ring-polymer instanton theory of electron transfer in the nonadiabatic limit. https://doi.org/10.1063/1.4932362

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