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arXiv · 2107.05092

Manifold curvature and Ehrenfest forces with a moving basis

Jessica F. K. Halliday·Emilio Artacho
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Abstract

Known force terms arising in the Ehrenfest dynamics of quantum electrons and classical nuclei, due to a moving basis set for the former, can be understood in terms of the curvature of the manifold hosting the quantum states of the electronic subsystem. Namely, the velocity-dependent terms appearing in the Ehrenfest forces on the nuclei acquire a geometrical meaning in terms of the intrinsic curvature of the manifold, while Pulay terms relate to its extrinsic curvature.

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Jessica F. K. Halliday, Emilio Artacho. 2021-07-11. Manifold curvature and Ehrenfest forces with a moving basis. https://doi.org/10.21468/scipostphys.12.1.020

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