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arXiv · 2211.09885

Curing the Divergence in Time-Dependent Density Functional Quadratic Response Theory

Davood Dar·Saswata Roy·Neepa T. Maitra
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Abstract

The adiabatic approximation in time-dependent density functional theory (TDDFT) is known to give an incorrect pole structure in the quadratic response function, leading to unphysical divergences in excited state-to-state transition probabilities and hyperpolarizabilties. We find the form of the exact quadratic response kernel and derive a practical and accurate approximation that cures the divergence. We demonstrate our results on excited state-to-state transition probabilities of a model system and of the LiH molecule.

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Davood Dar, Saswata Roy, Neepa T. Maitra. 2022-11-17. Curing the Divergence in Time-Dependent Density Functional Quadratic Response Theory. https://arxiv.org/abs/2211.09885

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