• To improve these results, we introduce a simple shifting procedure for XTPM that requires only a single fractional-occupancy SCF calculation per ex-citation energy. When used with B3LYP, this approach is accurate for both 1s → LUMO transitions (MAE = 0.3 eV) as well as higher-lying excitations (MAE = 0.6 eV), and is as accurate as the much more expensive BSE@G 0 W 0 method. Reasonable results for full XAS spectra (at several elemental K-edges) are obtained for the thymine and oxazole molecules, which were not in the data set used to determine the empirical shift parameter.