Q-Chem Webinar 6

The Electronic Couplings in Electron Transfer and Excitation Energy Transfer

Presented by Prof. Chao-Ping (Cherri) Hsu on 2013-03-06

Abstract

In recent years, research focusing on advanced materials and on molecular level of understanding in biological systems has attracted a lot of attention. One class of important reactions in this areas is the electron transfer (ET) process. Understanding of the corresponding electronic coupling becomes important since the coupling is an important parameter in the ET rate expression in the weak-coupling limit. Theoretical determination of ET coupling does not only provide a route to deeply understand the ET process, but also offers crucial hints to the designing of new functional molecules.

Electronic coupling is an important factor in the ET rate constant in the weak-coupling limit. We have developed several new methods for calculating ET coupling and have applied them to functional organic molecules. In addition, we are also interested in excitation energy transfer (EET), where excitation energy between two molecules/fragments is exchanged. The singlet-singlet EET is widely known as Forster's dipole-dipole interaction. We have recently studied the triplet-triplet EET, which is similar to the Dexter's exchange coupling. For the first time, ab initio triplet-triplet exchange coupling can be calculated and reported. Our results offer the basis to understanding previous experimental observation without additional mechanisms.