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arXiv · 2205.06690

Bethe Salpeter Equation Spectra for Very Large Systems

Nadine Bradbury·Minh Nguyen·Justin R Caram·Daniel Neuhauser
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Abstract

We present a highly efficient method for the extraction of optical properties of very large molecules via the Bethe-Salpeter equation. The crutch of this approach is the calculation of the action of the effective Coulombic interaction, $W$, through a stochastic TD Hartree propagation, which uses only 10 stochastic orbitals rather than propagating the full sea of occupied states. This leads to a scaling that is at most cubic in system size, with trivial MPI parallelization. We apply this new method to calculate the spectra and electronic density of the dominant excitons of a carbon-nanohoop bound fullerene system with 520 electrons, using less than 4000 core hours.

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Nadine Bradbury, Minh Nguyen, Justin R Caram, Daniel Neuhauser. 2022-05-23. Bethe Salpeter Equation Spectra for Very Large Systems. https://doi.org/10.1063/5.0100213

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