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arXiv · 0812.4338

Stochastic and deterministic molecular dynamics derived from the time-independent Schrödinger equation

Anders Szepessy
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Abstract

Ehrenfest, Born-Oppenheimer, Langevin and Smoluchowski dynamics are shown to be accurate approximations of time-independent Schrödinger observables for a molecular system avoiding caustics, in the limit of large ratio of nuclei and electron masses, without assuming that the nuclei are localized to vanishing domains. The derivation, based on a Hamiltonian system interpretation of the Schrödinger equation and stability of the corresponding Hamilton-Jacobi equation, bypasses the usual separation of nuclei and electron wave functions, includes crossing electron eigenvalues, and gives a different perspective on the Born-Oppenheimer approximation, Schrödinger Hamiltonian systems, stochastic electron equilibrium states and numerical simulation in molecular dynamics modeling.

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Anders Szepessy. 2010-01-12. Stochastic and deterministic molecular dynamics derived from the time-independent Schrödinger equation. https://arxiv.org/abs/0812.4338

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