Abstract
Recent developments in the ultrafast luminescence spectroscopy are reviewed. Principles of time-resolved luminescence measurements i.e., the optical Kerr shutter method and the up-conversion technique are described. The formation and relaxation processes of self-trapped excitons in quasi-one-dimensional halogenbridged platinum complexes (Pt-Cl, Pt-Br, Pt-I) are studied by luminescence up-conversion technique. The lifetime of the self-trapped excitons shows a systematic decrease as the mass of the halogen ion increases, showing the increased probability of non-radiative decay processes. The real-time capturing of the nuclear wave-packet form is successfully demonstrated in Pt-Br and good agreements with calculation are obtained. The luminescence in the picosecond region has been observed in the halogen-bridged nickel complex, and a coexistence of localized excitons with small and large lattice relaxations is suggested.
