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Title: Performance of periodic EOM-CCSD for bandgaps of inorganic semiconductors and insulators
We calculate bandgaps of 12 inorganic semiconductors and insulators composed of atoms from the first three rows of the Periodic Table using periodic equation-of-motion coupled-cluster theory with single and double excitations (EOM-CCSD). Our calculations are performed with atom-centered triple-zeta basis sets and up to 64 k-points in the Brillouin zone. We analyze the convergence behavior with respect to the number of orbitals and number of k-points sampled using composite corrections and extrapolations to produce our final values. When accounting for electron–phonon corrections to experimental bandgaps, we find that EOM-CCSD has a mean signed error of −0.12 eV and a mean absolute error of 0.42 eV; the largest outliers are C (error of −0.93 eV), BP (−1.00 eV), and LiH (+0.78 eV). Surprisingly, we find that the more affordable partitioned EOM-MP2 theory performs as well as EOM-CCSD.  more » « less
Award ID(s):
2023568
PAR ID:
10578054
Author(s) / Creator(s):
; ;
Publisher / Repository:
Chemical Physics
Date Published:
Journal Name:
The Journal of Chemical Physics
Volume:
160
Issue:
4
ISSN:
0021-9606
Format(s):
Medium: X
Sponsoring Org:
National Science Foundation
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