Prof. Nandini Ananth
Title: Modern Semiclassical Theory: Discovering Charge and Energy Transfer Mechanisms
Abstract:
This talk will introduce modern semiclassical (SC) theory as a versatile, efficient, and accurate quantum dynamics tool to discover the mechanisms of charge and energy transfer in complex chemical systems. SC theory offers access to systematically improvable dynamics, with classical-limit SC approximations able to describe coupled electron-nuclear dynamics beyond the Born-Oppenheimer limit, and capturing zero-point energy and shallow tunneling effects using just standard classical molecular dynamics trajectories. With some added computational expense, recently developed SC methods also open the door to going beyond the classical-limit to incorporate quantum coherence effects and deep tunneling. The broad applicability of SC theory is demonstrated through a comprehensive study of the photoisomerization and photofragmentation of ethylene with on-the-fly GPU-accelerated ab-initio forces and an investigation into the mechanisms of vibrational de-excitation at a metal surface. This talk will conclude with a brief description of ongoing work to characterize proton and electron transfer in the active site of a nitrification enzyme, cytP460, that will also serve to highlight outstanding challenges at the forefront of quantum dynamics theory development.
Keywords: Quantum dynamics, photochemistry, reaction mechanisms, semiclassical theory, nonadiabatic energy transfer, reactions at a metal surface
Faculty Host: Prof. Micheline Soley