Oleg Prezhdo (USC) Quantum Dynamics on Nanoscale

Excited state dynamics play key roles in numerous molecular and nanoscale materials designed for energy conversion. Controlling these far-from-equilibrium processes and steering them in desired directions require understanding of material’s dynamical response on the nanometer scale and with fine time resolution. We couple real-time time-dependent density functional theory for the evolution of electrons with non-adiabatic molecular dynamics for atomic motions to model such non-equilibrium response in the time-domain and at the atomistic level. The talk will introduce the simulation methodology [1] and discuss several exciting applications among the broad variety of systems and processes studied in our group [2,3], including metal halide perovskites, transition metal dichalcogenides, semiconducting and metallic quantum dots, metallic and semiconducting films, polymers, molecular crystals, graphene, carbon nanotubes, etc. Photo-induced charge and energy transfer, plasmonic excitations, Auger-type processes, energy losses and charge recombination create many challenges due to qualitative differences between molecular and periodic, and organic and inorganic matter. Our simulations provide a unifying description of quantum dynamics on the nanoscale, characterize the timescales and branching ratios of competing processes, resolve debated issues, and generate theoretical guidelines for development of novel systems.

[1] O. V. Prezhdo, “Modeling non-adiabatic dynamics in nanoscale and condensed matter systems”. Acc, Chem. Res. 54, 4239 (2021). 10.1021/acs.accounts.1c00525

[2] W. Li, Y. She, A. S. Vasenko, O. V. Prezhdo, “Ab initio nonadiabatic molecular dynamics of charge carriers in metal halide perovskites”, Nanoscale, 13, 10239-10265 (2021). 10.1039/D1NR01990B

[3] L. J. Wang, R. Long. O. V. Prezhdo, “Time-domain ab initio modeling of photoinduced dynamics at nanoscale interfaces”, Ann. Rev. Phys. Chem., 66, 54 (2015).   10.1021/ja408936j