An ab initio study on excited and ground state properties of the organic fluorescence probe PRODAN

Conformational energies of PRODAN (6-Propionyl-2-(dimethylamino)-naphthalene) have been calculated by Hartree-Fock ab initio methods as a function of the twisting and wagging motion of the amino and the rotational motion of the propionyl group. In agreement with experimental data, PRODAN is found planar in its optimum geometry. The CIS method is used to compute molecular orbital energies, excitation energies and dipole moments in dependence of the rotational isomerization of the dimethylamino group. The calculations allow the peculiar fluorescence properties of PRODAN to be explained by the TICT model. (C) 1997 Elsevier Science B.V.