Kohn-Sham effective potentials from FLOSIC using Ryabinkin-Kohut-Staroverov method

Density functional or beyond methods are often used in combination with photoelectron spectroscopy to obtain physical insights about the electronic structure of molecules and solids. The Kohn-Sham eigenvalues are not electron removal energies except for the highest occupied one, but they often, though not always, provide good approximations to electron binding energies (EBEs). Eigenvalues of the range separated hybrid functionals using tuned separation parameter generally provide good approximations to EBEs due to mitigation of self-interaction (SI) errors. We adapt and implement the Ryabinkin-Kohut-Staroverov method to obtain effective local potentials from the self-interaction corrected Fermi-Lowdin orbitals and density in the FLOSIC code. The density of states and HOMO-LUMO gaps obtained using this approach show much closer agreement with experimental values compared to those obtained with a range of DFA or functionals.