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arXiv · 2303.13787

Total Angular Momentum Conservation in Ab Initio Born-Oppenheimer Molecular Dynamics

Xuezhi Bian·Zhen Tao·Yanze Wu·Jonathan Rawlinson·Robert G. Littlejohn·Joseph E. Subotnik
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Abstract

We prove both analytically and numerically that the total angular momentum of a molecular system undergoing adiabatic Born-Oppenheimer dynamics is conserved only when pseudo-magnetic Berry forces are taken into account. This finding sheds light on the nature of Berry forces for molecular systems with spin-orbit coupling and highlights how ab initio Born-Oppenheimer molecular dynamics simulations can successfully capture the entanglement of spin and nuclear degrees of freedom as modulated by electronic interactions.

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Xuezhi Bian, Zhen Tao, Yanze Wu, Jonathan Rawlinson, Robert G. Littlejohn, Joseph E. Subotnik. 2023-03-24. Total Angular Momentum Conservation in Ab Initio Born-Oppenheimer Molecular Dynamics. https://doi.org/10.1103/physrevb.108.l220304

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