https://weizmann.zoom.us/j/93597285944?pwd=S0FJdHJ6eVpFTGJ3dHJHa3c1amJyUT09
Abstract:
A long-standing challenge within density functional theory (DFT) is the development of functionals that accurately predict the band gap and electronic structure of crystalline solids. A promising candidate for this task is the screened range-separated hybrid (SRSH) functional, which has been shown to yield accurate results for finite systems when one of the parameters in the functional, the range-separation parameter, is selected a priori. In the bulk limit, however, this parameter cannot be selected non-empirically based on the ionization potential theorem, owing to the delocalized electronic orbitals. Recently, we have developed a new method for the non-empirical tuning of the range-separation parameter, that is based on the removal of an electron in a state that corresponds to a Wannier function. We have applied the method to a set of systems ranging from narrow band gap semiconductors to large band gap insulators, obtaining fundamental band gaps in excellent agreement with experiment.
