Photoelectron spectra of early 3<i>d</i>-transition metal dioxide molecular anions from <i>GW</i> calculations

Photoelectron spectra of early 3d-transition metal dioxide anions, ScO2−, TiO2−, VO2−, CrO2−, and MnO2−, are calculated using semilocal hybrid density functional theory (DFT) many-body perturbation within the GW approximation one-shot perturbative eigenvalue self-consistent formalisms. Different levels compared with each other available photoelectron spectra. We show that a PBE0 starting point (G0W0@PBE0) consistently provides very good agreement for all experimentally measured binding energies (within 0.1 eV–0.2 eV or less). attribute this to success in mitigating self-interaction error providing quasiparticle wave functions, which renders first-order correction effective. One-shot calculations Perdew–Burke–Ernzerhof (PBE) do poorly predicting electron removal by underbinding orbitals typical errors near 1.5 eV. A higher exact exchange amount 50% DFT does not provide experiment overbinding 0.5 While as accurate G0W0@PBE0, G-only scheme W fixed PBE level reasonably predictive (typical 0.3 eV) describe these anions. Adding self-consistency also W, on hand, worsens overall. Our findings performance various methods discussed context our previous studies transition oxide molecular systems.