研究期間：10108~10207;This proposal aims to employ spectroscopic methods for studying the molecular structure and photochemistry of gaseous and solid-state molecules that play a key role in atmospheric chemistry or in materials science. On the basis of the spectroscopy techniques developed in our laboratory, we have successfully investigated the multiphoton photolysis reactions of bromomethanes (CHBr3, CHBr2Cl, CHBrCl2, and CH2Br2) at near-ultraviolet wavelengths, and will extend this study to more complicated systems such as iodomethanes (CHI3, CH2I2, and CH3I). In addition to the photochemistry of halomethanes, the electronic spectroscopy of triatomic free radicals is still of interest. Our group has studied the dispersed fluorescence spectroscopy of simple halocarbenes (CHX and CX2, X= Cl, Br) and GeCl2, but there still remain some unresolved issues such as the accurate singlet-triplet energy gap in CCl2 and that in CBr2. This proposal will continue this study and will study the electronic spectroscopy of other triatomic radicals related to semi-conductor manufacturing such as GeBr2, GeI2, and (GeCl2)2 van der Waals dimer. To unravel more detailed structure of these complicated triatomic radicals, double resonance (DR) experiment will be developed to record new electronic spectra of the interested molecules. The new spectroscopic data will benefit our basic understanding of molecular spectroscopy as well as the related chemical kinetics and dynamics. We are also interested in the spectroscopy of sold-state molecules including crystals containing trivalent lanthanide ions and metal nanoparticles. More than the well-developed excitation and photoluminescence spectroscopy techniques, we plan to apply these techniques to investigate the energy transfer processes such as up-conversion and second-harmonic generation (SHG) of crystals. The spectroscopic application on metal nanoparticles such as Raman spectra will be in continuous collaboration with other groups to explore possible applications of these molecules in materials science. If this proposal is supported, fruitful results could be expected in near future.
