Mixed quantum–classical dynamics
نویسنده
چکیده
We present a uniÐed derivation of the mean-Ðeld (Ehrenfest) and surfacehopping approaches to mixed quantumÈclassical dynamics that elucidates the underlying approximations of the methods and their strengths and weaknesses. We then report a quantitative test of alternative mixed quantumÈclassical methods against accurate quantum mechanical calculations for a simple one-dimensional curve-crossing model. We conclude that, for this model, surface-hopping with the adiabatic representation is decidedly superior to either mean-Ðeld or surface-hopping with the diabatic representation.
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