Condensed phase electron transfer beyond the Condon approximation

• Main Authors: Mavros, Michael G. (Author), Hait, Diptarka (Contributor), Van Voorhis, Troy (Contributor), Mavros, Michael George (Contributor)
• Format: Article
• Language: English
• Published: American Chemical Society (ACS), 2018-04-30T18:09:08Z.
• Subjects: Article
• Online Access: Get fulltext

 Condensed phase electron transfer problems are often simplified by making the Condon approximation: the approximation that the coupling connecting two charge-transfer diabatic states is a constant. Unfortunately, the Condon approximation does not predict the existence of conical intersections, which are ubiquitous in both gas-phase and condensed-phase photochemical dynamics. In this paper, we develop a formalism to treat condensed-phase dynamics beyond the Condon approximation. We show that even for an extremely simple test system, hexaaquairon(ii)/hexaaquairon(iii) self-exchange in water, the electronic coupling is expected to fluctuate rapidly and non-Condon effects must be considered to obtain quantitatively accurate ultrafast nonequilibrium dynamics. As diabatic couplings are expected to fluctuate substantially in many condensed-phase electron transfer systems, non-Condon effects may be essential to quantitatively capture accurate short-time dynamics.