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arXiv · 2609.34164

Basis Functions for Time-Dependent Kohn-Sham Inversion

Paul M. Zimmerman·Joshua Kammeraad·Duy-Khoi Dang·Harish S. Bhat
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Abstract

Floquet theory provides insight into the inversion of time-dependent Kohn-Sham density functional theory. Specifically, mathematical derivations show that the fundamental frequencies of a time-dependent wavefunction solution are the leading-order harmonics for the TD-KS state. Numerical tests of the resulting ansatz in 1D and 3D for atomic and molecular cases demonstrate its utility. In particular, low $L_{2}$ errors in the time-dependent density and longitudinal current were found, even though currents were not an explicit optimization objective. In all, the proposed inversion ansatz provides exchange-correlation potentials from time-dependent wavefunctions, is highly interpretable, and may significantly help in the development of nonadiabatic density functionals.

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Paul M. Zimmerman, Joshua Kammeraad, Duy-Khoi Dang, Harish S. Bhat. 2026-09-28. Basis Functions for Time-Dependent Kohn-Sham Inversion. https://arxiv.org/abs/2609.34164

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