Abstract
The thesis focuses on titanium phosphites/phosphates and metal-center modifications in 40-ring-channel bimetal phosphites. Five compounds synthesized by hydrothermal method were characterized by single crystal X-ray diffraction; their purity was examined by comparing powder diffraction patterns with theoretical patterns and their physical properties was also measured. These compounds are grouped into A, B series to discuss. A series includes three titanium phosphites/phosphates [Ti2(HPO3)3 (A1), (H3O)[Ti3(HPO3)6] (A2), (H3tren)[TiZn3(HPO4)2(PO4)3](A3)] with different oxidation state. A1 is the first three-valent titanium(III) phosphite. The structure consists of distorted TiO6 octahedra which share faces to form a dimeric Ti2O9 unit. These dimers are interlinked by the phosphite groups, which link into a three-dimensional arrangement having 12R channel. The compounds are isostructural with Fe2(HPO3)3. A2 is the mixed-valent titanium(III)/(IV) phosphite. It is made of octahedrally coordinated titanium and tetrahedrally coordinated phosphorus centers to build 4R chain, and chains were linked into novel three-dimensional structure. A3 is two-dimensional titanium(IV) zincophosphate. Its inorganic layers consist TiO6 octahedra and ZnO4, HPO4 and PO4 tetrahedra. Its irremovable template, H3tren3+ ion, forms strong hydrogen bonding on the [TiZn3(HPO4)2(PO4)3]3- to balance the charge of inorganic layers. B series discusses on gallium zincophosphites system with 40-ring-channel (40R-NTHU-13). Without changing the structure, trivalent metal ion, Ga3+ could be completely replaced by Al3+ and Fe3+, namely 40R-Al and 40R-Ga. Transition metal ions, such as Mn2+, Fe2+, Co2+, Ni2+, Cu2+ can also be separately incorporated into six-coordinated Zn2+ center in structure. The metal-incorporated positions and amounts can be clearly characterized. In this series, we successfully insert five metal ions into the framework and make the metal center exchangeable, which render the material from diamagnetic to anti-ferromagnetic. In this research, two series have been developed by strategic experiments, and both structures and properties of all compounds are creative. In future, many possibilities on these series for continuing more investigation are promising.