Sparse-Stochastic Fragmented Exchange for Large-Scale Hybrid Time-Dependent Density Functional Theory Calculations

Sereda, Mykola; Allen, Tucker; Bradbury, Nadine C.; Ibrahim, Khaled Z.; Neuhauser, Daniel

doi:10.1021/acs.jctc.4c00260

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Sparse-Stochastic Fragmented Exchange for Large-Scale Hybrid Time-Dependent Density Functional Theory Calculations

Sereda, Mykola·Allen, Tucker·Bradbury, Nadine C.·Ibrahim, Khaled Z.·Neuhauser, Daniel

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Abstract

Here we extend our recently developed sparse-stochastic fragmented exchange formalism for ground-state near-gap hybrid DFT to calculate absorption spectra within linear-response time-dependent generalized Kohn-Sham DFT (LR-GKS-TDDFT) for systems consisting of thousands of valence electrons within a grid-based/plane-wave representation. A mixed deterministic/fragmented-stochastic compression of the exchange kernel, here using long-range explicit exchange functionals, provides an efficient method for accurate optical spectra. Both real-time propagation as well as frequency-resolved Casida-equation-type approaches for spectra are presented, and the method is applied to large molecular dyes.

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Sereda, Mykola, Allen, Tucker, Bradbury, Nadine C., Ibrahim, Khaled Z., Neuhauser, Daniel. 2024-05-07. Sparse-Stochastic Fragmented Exchange for Large-Scale Hybrid Time-Dependent Density Functional Theory Calculations. https://doi.org/10.1021/acs.jctc.4c00260

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