We calculate the band gaps 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 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 band gaps, we find that EOM-CCSD has a mean signed error of
β0.12 eV and a mean absolute error of 0.42 eV; the largest outliers are C
(error of β0.93 eV), BP (β1.00 eV), and LiH (+0.78 eV). Surprisingly, we
find that the more affordable partitioned EOM-MP2 theory performs as well as
EOM-CCSD.Comment: 6 pages, 5 figures, 1 tabl