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Using Cyclic Voltammetry, UV-Vis-NIR, and EPR Spectroelectrochemistry to Analyze Organic Compounds
Published on: October 18, 2018
Exciton/Charge-Transfer Electronic Couplings in Organic Semiconductors
Seth Difley1, Troy Van Voorhis1
1Department of Chemistry, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139-4307, United States.
Abstract:
Charge transfer (CT) states and excitons are important in energy conversion processes that occur in organic light emitting devices (OLEDS) and organic solar cells. An ab initio density functional theory (DFT) method for obtaining CT-exciton electronic couplings between CT states and excitons is presented. This method is applied to two organic heterodimers to obtain their CT-exciton coupling and adiabatic energy surfaces near their CT-exciton diabatic surface crossings. The results show that the new method provides a new window into the role of CT states in exciton-exciton transitions within organic semiconductors.
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