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Title: Combining localized orbital scaling correction and Bethe–Salpeter equation for accurate excitation energies
We applied localized orbital scaling correction (LOSC) in Bethe–Salpeter equation (BSE) to predict accurate excitation energies for molecules. LOSC systematically eliminates the delocalization error in the density functional approximation and is capable of approximating quasiparticle (QP) energies with accuracy similar to or better than GW Green’s function approach and with much less computational cost. The QP energies from LOSC, instead of commonly used G 0 W 0 and ev GW, are directly used in BSE. We show that the BSE/LOSC approach greatly outperforms the commonly used BSE/ G 0 W 0 approach for predicting excitations with different characters. For the calculations of Truhlar–Gagliardi test set containing valence, charge transfer, and Rydberg excitations, BSE/LOSC with the Tamm–Dancoff approximation provides a comparable accuracy to time-dependent density functional theory (TDDFT) and BSE/ev GW. For the calculations of Stein CT test set and Rydberg excitations of atoms, BSE/LOSC considerably outperforms both BSE/ G 0 W 0 and TDDFT approaches with a reduced starting point dependence. BSE/LOSC is, thus, a promising and efficient approach to calculate excitation energies for molecular systems.  more » « less
Award ID(s):
1900338
NSF-PAR ID:
10333212
Author(s) / Creator(s):
; ; ;
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
156
Issue:
15
ISSN:
0021-9606
Page Range / eLocation ID:
154101
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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