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Oleg V Prezhdo

Professor of Chemistry
Physical and Theoretical chemistry

Ph.D. 1997, University of Texas at Austin
Office: SSC 414
Phone: (213) 821-3116
Fax: (213) 740-2701
Email: prezhdo@usc.edu
 Group Homepage


Research Focus

 

The research goal of the Prezhdo group is to obtain a theoretical understanding at the molecular level of chemical reactivity and energy transfer in complex condensed-phase chemical and biological environments. This requires the development of new theoretical and computational tools and the application of these tools to challenging chemical problems in direct connection to experiments. Quantum mechanics, in principle, may be used to describe any chemical process. Its application to systems containing more than a dozen atoms, however, is nearly impossible due to computational constraints. Classical mechanics, on the other hand, may be easily applied to systems of thousands of atoms. Fortunately, in a given chemical system, only a small subset of the particles involved must be treated quantum-mechanically. This has allowed our group to develop a number of mixed quantum- classical approaches that are suitable for different situations. Quantized Hamilton Dynamics, for example, provides a beautiful and remarkably simple extension of classical mechanics that incorporates zero-point motion, tunneling, dephasing and other quantum effects. The Stochastic Mean Field approach deals with chemical reactions involving quantum transitions, such as absorption and emission of light, and conversion of light and electric energy to forming and breaking chemical bonds. Chemical versions of the Schrodinger Cat paradox, the "watched pot never boils", and quantum Zeno effects are other important phenomena that may be modeled with the Stochastic Mean Field approach. The Bohmian or hydrodynamic interpretation of quantum mechanics is used to couple quantum and classical variables and to interpret results in terms of intuitive particle trajectories. These varied quantum-classical approaches are being implemented within the framework of time-dependent density functional theory.

The Prezhdo group pioneered ab initio real-time simulations of the ultrafast electron transfer across the molecule-semiconductor interface that drives Gratzel-type solar cells. Organic-inorganic interfaces are critical in molecular electronics and remain the field's least understood components. We have established electron-transfer mechanisms that suggest ways to improve solar cell efficiencies. Motivated by recent experiments, we are modeling charge dynamics in semiconductor and metallic nanoparticles, carbon nanotubes and nanoribbons, and related nanoscale systems. Time-domain atomistic simulations of interactions between charges, spins and phonons in these materials create the theoretical basis for photovoltaic devices, optical and conductance switches, quantum wires, logic gates, miniature field-effect transitions and lasers.

Our group has developed the simplest and most used model of biological catch-binding, a fascinating biological phenomenon whereby the application of a pulling force increases bond lifetime (!). We created a physically intuitive description of catch-binding and derived universal laws that unite experimental data obtained through different pulling regimes. We are investigating the atomic origin of catch-binding by steered molecular dynamics and study other counter-intuitive force- induced effects in molecular biology, such as force- induced allostery. New generations of electro-optic devices based on polymers showing order-disorder transitions are being designed by colleagues in Chemistry and Chemical Engineering. Our group developed a statistical- mechanical model of the ordering that clearly explains how the efficiency of the polymeric materials depends on molecular structure, temperature, electric field and other tunable parameters.

Members of the Prezhdo group use both pen-and-paper and computers in their research.

Selected publications

 

View full publication list in Dr. Prezhdo group website

Chu, WB; Saidi, WA; Zheng, QJ; Xie, Y; Lan, ZG; Prezhdo, OV; Petek, H; Zhao, J. "Ultrafast Dynamics of Photongenerated Holes at a CH3OH/TiO2 Rutile Interface." Journal of the American Chemical Society (2016). 138 (41), pp 13740-13749

Dong, S; Pal, S; Lian, J; Chan, Y; Prezhdo, OV; Loh, ZH. "Sub-Picosecond Auger-Mediated Hole-Trapping Dynamics in Colloidal CdSe/CdS Core/Shell Nanoplatelets." ACS Nano (2016). 10 (10), pp 9370-9378

Nebgen, B; Prezhdo, OV. "Fragment Molecular Orbital Nonadiabatic Molecular Dynamics for Condensed Phase Systems." Journal of Physical Chemistry A (2016). 120 (36), pp 7205-7212 

Long, R; Fang, WH; Prezhdo, OV. "Moderate Humidity Delays Electron-Hole Recombination in Hybrid Organic-Inorganic Perovskites: Time-Domain Ab Initio Simulations Rationalize Experiments." Journal of Physical Chemistry Letters (2016). 7 (16), pp 3215-3222

Korsun, OM; Kalugin, ON; Fritsky, IO; Prezhdo, OV. "Ion Association in Aprotic Solvents for Lithium Ion Batteries Requires Discrete-Continuum Approach: Lithium Bis(oxalato)borate in Ethylene Carbonate Based Mixtures."  Journal of Physical Chemistry C (2016). 120 (30), pp 16545-16552

Chaban, VV; Prezhdo, OV. "Haber Process Made Efficient by Hydroxylated Graphene: Ab Initio Thermochemistry and Reactive Molecular Dynamics." Journal of Physical Chemistry Letters (2016). 7 (13), pp 2622-2626

Zhou, ZH; Han, FS; Guo, LJ; Prezhdo, OV. "Understanding divergent behaviors in the photocatalytic hydrogen evolution reaction on CdS and ZnS: a DFT based study." Physical Chemistry Chemical Physics (2016). 18 (25), pp 16862-16869

Chaban, VV; Prezhdo, OV. "Ab Initio Molecular Dynamics of Dimerization and Clustering in Alkali Metal Vapors." Journal of Physical Chemistry A (2016). 120 (25), pp  4302-4306 

Sifain, AE; Wang, LJ; Prezhdo, OV. "Communication: Proper treatment of classically forbidden electronic transitions significantly improves detailed balance in surface hopping." Journal of Chemical Physics (2016). 144 (21)

Wang, LJ; Akimov, A; Prezhdo, OV. "Recent Progress in Surface Hopping: 2011-2015." Journal of Physical Chemistry Letters (2016). 7 (11), pp 2100-2112

Chaban, VV; Prezhdo, OV. "Ionic Vapor Composition in Pyridinium-Based Ionic Liquids." Journal of Physical Chemistry B (2016). 120 (25), pp 4661-4667  

Chaban, VV; Prezhdo, OV. "Ionic Vapor Composition in Critical and Supercritical States of Strongly Interacting Ionic Compounds." Journal of Physical Chemistry B (2016). 120 (18), pp 4302-4309 

Ranasingha, O; Wang, H; Zobac, V; Jelinek, P; Panapitiya, G; Neukirch, AJ; Prezhdo, OV; Lewis, JP. "Slow Relaxation of Surface Plasmon Excitations in Au-55: The Key to Efficient Plasmonic Heating in Au/TiO2." Journal of Physical Chemistry Letters (2016). 7 (8), pp 1563-1569

Pal, S; Trivedi, DJ; Akimov, AV; Aradi, B; Frauenheim, T; Prezhdo, OV. "Nonadiabatic Molecular Dynamics for Thousand Atom Systems: A Tight-Binding Approach toward PYXAID." Journal of Chemical Theory and Computation (2016). 12 (4), pp 1436-1448

Long, R; Liu, J; Prezhdo, OV. "Unravelling the Effects of Grain Boundary and Chemical Doping on Electron-Hole Recombination in CH3NH3PbI3 Perovskite by Time-Domain Atomistic Simulation." Journal of the American Chemical Society (2016). 138 (11), pp 3884-3890

Chaban, VV; Prezhdo, OV. "Electron Solvation in Liquid Ammonia: Lithium, Sodium, Magnesium, and Calcium as Electron Sources." Journal of Physical Chemistry B (2016). 120 (9), pp 2500-2506 

Preske, A; Liu, J; Prezhdo, OV; Krauss, TD. "Large-Scale Programmable Synthesis of PbS Quantum Dots." ChemPhysChem (2016). 17 (5), pp 681-686 

Long, R; Prezhdo, OV. "Quantum Coherence Facilitates Efficient Charge Separation at a MoS2/MoSe2 van der Waals Junction." Nano Letters (2016). 16 (3), pp 1996-2003

Chen, X; Prezhdo, OV; Ma, ZY; Hou, TJ; Guo, ZY; Li, YY. "Ab initio phonon-coupled nonadiabatic relaxation dynamics of [Au-25(SH)(18)](-) clusters." Physica Status Solidi (B) - Basic Solid State Physics (2016). 253 (3), pp 458-462

Chaban, VV; Prezhdo, OV. "Boron doping of graphene-pushing the limit." Nanoscale (2016). 8 (34), pp 15521-15528

Chaban, VV; Prezhdo, OV. "Pressure-driven opening of carbon nanotubes." Nanoscale (2016). 8 (11), pp 6014-6020

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