A facile synthesis route for preparing SBA-15 silica of platelet shape and very short mesochannels (150-350 nm) was developed by introducing a small amount of Zr(IV) ions in the synthesis solution.The synthesis route can be easily extended to prepare platelet SBA-15 materials with various organic functional groups up to 1.87 mmol/g loading in one pot. In situ XRD and freeze-fracture replication TEM were found to be powerful techniques for studying the self-assembly processes. The platelet SBA-15 with short mesochannels in 150-350 nm was formed because of the fast self-assembly rate of P123 micelles and TEOS accelerated by the Zr(IV) ions in the synthesis solution. The platelet SBA-15 materials are superior to the conventional SBA-15 of rod or fiber morphologies in facilitating molecular diffusion and less possibility of pore blockage when used in the sorption or reactions of bulky molecules.

Light-induced excited spin state trapping of Fe(phen) 2 (NCS) 2 is studied by X-ray absorption spectroscopy using synchrotron radiation. The molecular structure of the excited high-spin state at 17 K is investigated by EXAFS. The relaxation of the light-induced high-spin state at various temperatures is monitored through the absorption spectra. The concurrent abrupt lattice change with the change in electronic configuration is observed through single crystal X-ray diffraction. The lattice cooperative effect is important in the relaxation behavior. The magnetic property and the relaxation behavior of two differently prepared samples are distinctly different.

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