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Time-reversible Born-Oppenheimer molecular dynamics

Anders M. N. Niklasson·C. J. Tymczak·Matt Challacombe
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Abstract

We present a time-reversible Born-Oppenheimer molecular dynamics scheme, based on self-consistent Hartree-Fock or density functional theory, where both the nuclear and the electronic degrees of freedom are propagated in time. We show how a time-reversible adiabatic propagation of the electronic degrees of freedom is possible despite the non-linearity and incompleteness of the self-consistent field procedure. Time-reversal symmetry excludes a systematic long-term energy drift for a microcanonical ensemble and the number of self-consistency cycles can be kept low (often only 2-4 cycles per nuclear time step) thanks to a good initial guess given by the adiabatic propagation of the electronic degrees of freedom. The time-reversible Born-Oppenheimer molecular dynamics scheme therefore combines a low computational cost with a physically correct time-reversible representation of the dynamics, which preserves a detailed balance between propagation forwards and backwards in time.

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Anders M. N. Niklasson, C. J. Tymczak, Matt Challacombe. 2006-04-28. Time-reversible Born-Oppenheimer molecular dynamics. https://doi.org/10.1103/physrevlett.97.123001

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