Theoretical simulation of molecular valence and core photoemission spectra with GW approaches

The GW methodology provides an explicit interpretation of charged excited states in chemical system. As a result, it has been used extensively to investigate theoretical spectroscopy of both periodic crystalline structure and small molecules. Here we present our finite temperature GW methods with different levels of consistency (for example, scGW and G0W0), which provides accurate estimation of valence electron photoexcitation spectra for molecules. We compare the results with both experimental energies and CCSD(T) references. In addition to the well-benchmarked test of valence excitation on the GW100 set, we also demonstrate that our GW schemes can be used to render inner shell photoemission spectra using accurate analytical continuation. Additional entries involving transitional metals were included to the GW100 subset for core level spectra. We also examine how the GW results compare with Delta methods (ΔHF and ΔCC).