Spin-orbit interactions in heterocyclic analogues of fluorene

Abstract

For carbazole, dibenzofuran, and dibenzothiophene—heterocyclic analogues of fluorene containing N-H, O, and S groups, respectively—the transition dipole moments P 00 i for the transitions 3 B 2→S 0 and 3 A 1→S 0 from the sublevels i=z, y, x of the triplet electronic ππ* states, which are caused by intramolecular spin-orbit (SO) interactions, are calculated. The effect that the SO coupling between the S 0 state and highest triplet states has on the calculation results is considered. The effects exerted on the value of P 00 i by such specific features of the molecular structure as the position of a heteroatom on the symmetry axis, its valence, and different constants of SO coupling in heteroatoms are discussed. The reason for the weak influence of the quantity ςHA on the rate constant of radiative deactivation of the lowest T state is ascertained.