Physics ABC Seminar: "Energy level alignment at molecule-substrate interfaces from first principles: Challenges and new developments", Prof. Zhenfei Liu, Wayne State University

Warning Icon This event is in the past.

Date: September 15, 2020
Time: 3:30 p.m. - 4:30 p.m.
Location: Zoom
Category: Seminar
Energy level alignment at molecule-substrate interfaces from first principles: Challenges and new developments
Zhenfei Liu
Department of Chemistry, Wayne State University

Molecule-substrate interfaces are ubiquitous in nanoscale functional materials and energy related applications. Characterizing the electronic structure at molecule-substrate interfaces, especially the energy level alignment between molecular frontier orbitals and the Fermi level of the substrate, is crucial for understanding interfacial charge dynamics. Density functional theory (DFT) has been successful in computing binding geometries and adsorption energies, but much less successful in predicting level alignments. This is because the latter depends on quasiparticle excitation energies, typically believed to be outside the reach of DFT. Many-body perturbation theory, such as the GW approach, provides a formal theoretical framework for quasiparticle energies, but the computational cost for typical interfaces is high. In this talk, I will introduce two methodological advancements for accurate and efficient calculations of level alignments at weakly coupled molecule-substrate interfaces: (1) an optimally tuned range-separated hybrid functional, taking into account the substrate screening effect via the image-charge model; and (2) a novel GW approach employing the additivity of the Kohn-Sham polarizability for the interface, which significantly reduces the computational cost compared to direct GW calculations.

Topic: Condensed Matter & Biophysics Seminars
Join Zoom Meeting
Meeting ID: 994 2731 8204
Passcode: 033343
One tap mobile
+16468769923,,99427318204#,,,,,,0#,,033343# US (New York)
+13017158592,,99427318204#,,,,,,0#,,033343# US (Germantown)
Dial by your location
        +1 646 876 9923 US (New York)
        +1 301 715 8592 US (Germantown)
        +1 312 626 6799 US (Chicago)
        +1 253 215 8782 US (Tacoma)
        +1 346 248 7799 US (Houston)
        +1 408 638 0968 US (San Jose)
        +1 669 900 6833 US (San Jose)
Meeting ID: 994 2731 8204
Passcode: 033343
Find your local number:


Zhi-Feng Huang


September 2020