English

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

Chemical Physics 2023-05-01 v3

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.

Keywords

Cite

@article{arxiv.2211.09885,
  title  = {Curing the Divergence in Time-Dependent Density Functional Quadratic Response Theory},
  author = {Davood Dar and Saswata Roy and Neepa T. Maitra},
  journal= {arXiv preprint arXiv:2211.09885},
  year   = {2023}
}
R2 v1 2026-06-28T06:09:56.388Z