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arXiv · 1606.06110

Electronic friction near metal surfaces: a case where molecule-metal couplings depend on nuclear coordinates

Wenjie Dou·Joseph E. Subotnik
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Abstract

We derive an explicit form for the electronic friction as felt by a molecule near a metal surface for the general case that molecule-metal couplings depend on nuclear coordinates. Our work generalizes a previous study by von Oppen et al [Beilstein Journal of Nanotechnology, 3, 144, 2012], where we now go beyond the Condon approximation (i.e. molecule-metal couplings are not held constant). Using a non-equilibrium Green's function formalism in the adiabatic limit, we show that fluctuating metal-molecule couplings lead to new frictional damping terms and random forces, plus a correction to the potential of mean force. Numerical tests are performed and compared with a modified classical master equation; our results indicate that violating the Condon approximation can have a large effect on dynamics.

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Wenjie Dou, Joseph E. Subotnik. 2016-06-20. Electronic friction near metal surfaces: a case where molecule-metal couplings depend on nuclear coordinates. https://doi.org/10.1063/1.4965823

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