| Summary: | 博士 === 國立清華大學 === 化學系 === 101 === 12 compounds synthesized by hydrothermal and ionothermal methods were characterized by single crystal X-ray diffraction; their purity was examined by comparing powder diffraction patterns with theoretical patterns and their physical properties were also measured. These compounds are grouped into three systems based on different metal centers,
frameworks or optical properties, namely System A, B and C.
System A includes three vanadium(III) phosphites (A1-A3), which were synthesized for the first time by vanadium(IV) sulfate with the same organic template, i.e. the cyclic-type
amine cyclohexylamine. A1 possesses intersecting 2D extra large 16R channels, with solvent accessible volume reaches up to 45%. Solid state redox property was achieved in A1 by
losing and regaining coordinating water ligand and possibly contributed by the incorporated boron which plays an important role in stabilizing the structure. With zinc oxide (ZnO), a bimetal vanadium zincophosphite A2 was obtained, featured with a double layered structure. Furthermore, by replacing ZnO with gallium oxide, a rare chiral structure A3 was prepared.
System B includes six non-centrosymmetric and optical compounds (B1-B6). B1 is a tin(II) phosphite with obvious second harmonic generation signal, with intrinsic white light emission. With identical structure with B1, B2 possesses higher white light quantum efficiency by doping manganese(II). B3 and B4 are polymorphs, both of which are neutral zinc oxalatophosphite structure. Even though both structures are strongly related, their optical properties are quite different. Without precedent, the use of sucrose as chiral induction reagent has been proved to be an effective route for synthesizing B5 and B6, two 20R non-centrosymmetric structures never revealed.
System C includes three compounds (C1-C3), whose structures were all induced by aliphatic monoamines with different straight carbon-chain-length. The incorporation of
manganese(II) in 40R gallium zincophosphite C1 contributed to intrinsic white light emission. The mesolamellar gallium phosphite C2 possesses almost 3 nm interlayer distance. C3 can be regarded as the structural expansion of C1, creating the channel size from 40R to amazing 64R. By using specific type of organic templates, the channel size and the structural connectivity can be well controlled and redicted. Besides, considering the meso-scale interlayer distance and pore size in C2 and C3, obtaining single crystals for structure characterization of both compounds was unprecedentedly achieved.
In this research, three systems have been developed by strategic experiments, and both structures and properties of all compounds are creative and inspiring. More possibilities on these systems for continuing further investigation are promising in future.
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