How to recover Marcus theory with fewest switches surface hopping: Add just a touch of decoherence

We present a slightly improved version of our augmented fewest switches surface hopping (A-FSSH) algorithm and apply it to the calculation of transition rates between diabatic electronic states within the spin-boson model. We compare A-FSSH rates with (i) Marcus rates from the golden rule, (ii) Tully-style FSSH rates, and (iii) FSSH rates using a simple, intuitive decoherence criterion. We show that unlike FSSH, A-FSSH recovers the correct scaling with diabatic coupling (quadratic in V) as well as the lack of dependence on harmonic frequency omega for small enough values of omega and large enough temperatures. (C) 2012 American Institute of Physics. [http://dx.doi.org/10.1063/1.4733675]