Study on dynamic optical nonlinearities of excited state proton transfer in ethanol solution of 7-hydroxyquinoline

The dynamic process of 7-hydroxyquinoline with excited state proton transfe r has been studied by the pump-probe method in which a three-dimensional de generate four-wave mixing technique is employed for the probe. The molecula r hyperpolarizability and lifetime of the excited state involved in the exc ited state proton transfer process of 7-hydroxyquinoline are obtained in ou r experiment. The decay time of the cation excited state is 35 ps and the d ecay time of the anion excited state is 250 ps. The molecular hyperpolariza bility of 7-hydroxyquinoline in the enol form ground state, cation excited state and anion excited state are 1.3 +/- 0.2 X 10(-31), 8.0 +/- 1.0 X 10(- 31) and 5.8 +/- 0.8 X 10(-30) esu, respectively. (C) 2000 Elsevier Science B.V. All rights reserved.