Date:
Thu, 23/06/2022 - 11:00 to 12:00
Location:
Los Angeles Bld., Jerusalem, Israel
Abstract:
In work with Tamar Stein and Roi Baer some ten years ago, we turned the concept of optimal tuning of range-separated hybrid functionals into an important tool for overcoming the fundamental gap problem and the charge transfer excitation problem in molecular systems. In this talk, I will briefly remind of this concept and its consequences. I will then focus on the difficulty of extending these ideas to the solid state, and how the challenge was finally overcome by means of introducing dielectric screening into the functional form and
localization into the tuning procedure. This approach, couched rigorously within the generalized Kohn-Sham formalism of density functional theory, can quantitatively produce the same one- and two-quasi-particle excitation picture given by many-body perturbation theory (MBPT), without any empiricism. Practical applications will be given and remaining challenges and opportunities will be discussed.
In work with Tamar Stein and Roi Baer some ten years ago, we turned the concept of optimal tuning of range-separated hybrid functionals into an important tool for overcoming the fundamental gap problem and the charge transfer excitation problem in molecular systems. In this talk, I will briefly remind of this concept and its consequences. I will then focus on the difficulty of extending these ideas to the solid state, and how the challenge was finally overcome by means of introducing dielectric screening into the functional form and
localization into the tuning procedure. This approach, couched rigorously within the generalized Kohn-Sham formalism of density functional theory, can quantitatively produce the same one- and two-quasi-particle excitation picture given by many-body perturbation theory (MBPT), without any empiricism. Practical applications will be given and remaining challenges and opportunities will be discussed.