All-electron Gaussian-based GW methods for periodic systems

Abstract

We describe an all-electron GW implementation for periodic systems with k-point sampling using a cryst. Gaussian basis. Due to the compactness of Gaussian bases, no virtual state truncation is required as is seen in many plane-wave formulations. Using our implementation, we study quasiparticle energies and band structures across a range of systems including semiconductors, rare gas solids, and metals. We find that the G₀W₀ band gaps of traditional semiconductors converge rapidly with respect to the basis size, even for the conventionally challenging case of ZnO. Using correlation-consistent bases of polarized triple-zeta quality, we find the mean abs. relative error of the extrapolated G₀W₀@PBE band gaps to be only 5.2% when compared to exptl. values. For core excitation binding energies, we find that G₀W₀ predictions improve significantly over those from DFT, esp. when the G₀W₀ calcns. are started from hybrid functionals with a high percentage of exact exchange.