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

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

doi:10.1021/acs.jctc.4c00260

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

J Chem Theory Comput. 2024 May 7. doi: 10.1021/acs.jctc.4c00260. Online ahead of print.

Authors

Mykola Sereda¹, Tucker Allen¹, Nadine C Bradbury¹, Khaled Z Ibrahim², Daniel Neuhauser¹

Affiliations

¹ Department of Chemistry and Biochemistry, and California Nanoscience Institute, UCLA, Los Angeles, California 90095-1569, United States.
² Computer Science Department, Lawrence Berkeley National Laboratory, One Cyclotron Road, Berkeley, California 94720, United States.

PMID: 38713513
DOI: 10.1021/acs.jctc.4c00260

Abstract

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.