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arXiv · 2211.07179

Photoionization and core resonances from range-separated time-dependent density-functional theory for open-shell states: Example of the lithium atom

Julien Toulouse·Karno Schwinn·Felipe Zapata·Antoine Levitt·Eric Cancès·Eleonora Luppi
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Abstract

We consider the calculations of photoionization spectra and core resonances of open-shell systems using range-separated time-dependent density-functional theory. Specifically, we use the time-dependent range-separated hybrid (TDRSH) scheme, combining a long-range Hartree-Fock (HF) exchange potential and kernel with a short-range potential and kernel from a local density-functional approximation, and the time-dependent locally range-separated hybrid (TDLRSH) scheme, which uses a local range-separation parameter. To efficiently perform the calculations, we formulate a spin-unrestricted linear-response Sternheimer approach in a non-orthogonal B-spline basis set and using appropriate frequency-dependent boundary conditions. We illustrate this approach on the Li atom, which suggests that TDRSH and TDLRSH are adequate simple methods for estimating single-electron photoionization spectra of open-shell systems.

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Julien Toulouse, Karno Schwinn, Felipe Zapata, Antoine Levitt, Eric Cancès, Eleonora Luppi. 2022-11-14. Photoionization and core resonances from range-separated time-dependent density-functional theory for open-shell states: Example of the lithium atom. https://doi.org/10.1063/5.0134645

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