DIRECT ESTIMATE OF THE ELECTRONIC COUPLING DRIVING THE PHOTOCHEMICAL PROTON-TRANSFER IN ACRIDINE-DOPED FLUORENE CRYSTAL

The electronic coupling integral J of a photochemical hydrogen abstraction in an acridine-doped fluorene crystal was estimated in order to clarify the controversial question of its driving force. The features of the reaction system strongly motivate the adoption of the "diabatic" procedure for calculating J instead of its calculation as an adiabatic quantity. A simple model was applied for direct construction of the diabatic states employing a single determinant presentation of the wavefunctions, AOs being Slater orbitals. The present estimates support the previously made conclusion from the analysis of the kinetic data based on a golden-rule approach generalized for arbitrary values of the coupling, that J is mainly responsible for the unusually rapid reaction.