NAC-TDDFT: Time-dependent density functional theory for nonadiabatic couplings

Zikuan Wang; Chenyu Wu; Wenjian Liu

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arXiv · 2105.10804

NAC-TDDFT: Time-dependent density functional theory for nonadiabatic couplings

Zikuan Wang·Chenyu Wu·Wenjian Liu

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Abstract

First-order nonadiabatic coupling matrix elements (fo-NACMEs) are the basic quantities in theoretical descriptions of electronically nonadiabatic processes that are ubiquitous in molecular physics and chemistry. Given the large size of systems of chemical interests, time-dependent density functional theory (TDDFT) is usually the first choice. However, the lack of wave functions in TDDFT renders the formulation of NAC-TDDFT for fo-NACMEs conceptually difficult. The present account aims to analyze the available variants of NAC-TDDFT in a critical but concise manner and meanwhile point out the proper ways for implementation. It can be concluded, from both theoretical and numerical points of view, that the equation of motion-based variant of NAC-TDDFT is the right choice. Possible future developments of this variant are also highlighted.

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Zikuan Wang, Chenyu Wu, Wenjian Liu. 2021-05-22. NAC-TDDFT: Time-dependent density functional theory for nonadiabatic couplings. https://arxiv.org/abs/2105.10804

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