| Inorganic microporous materials have popular applications in catalysis, adsorption, ion-exchange, separation and host-guest assemblies due to their unique pore architectures. And the rational design and synthesis of new microporous compounds, as well as the development of new synthetic ways are becoming the central topic of microporous materials chemistry. Zeolites (aluminosilicates) are the most well-known microporous molecular sieves. During the past decades, a huge number of new zeolite-like inorganic solids like phosphates, arsenates, germanates, phosphite, sulfate, selenite, carbonate and supertetrahedral sulfides have been synthesized and characterized. The successful syntheses of these new compounds with open-framework open a new field for the microporous compounds. As a new class of inorganic microporous materials, metal phosphites exhibit rich structural and compositional diversity. Since Harrison et al. reported the first organically templated zinc phosphite in 2000, considerable interest in the study of organically templated zinc phosphites has been aroused. Up to date, a number of zinc phosphites with 0D cluster, 1D chain, 2D layer and 3D open-framework structures have been reported. Compared to tetrahedral phosphate group [PO4]3-, the pyramidal phosphite group [HPO3]2- can only make three P-O-Zn bonds, thus, some more significant structures which are different from those formed by phosphate group have been isolated. The goal of this work is to synthesis and preparation of zinc phosphites continuously and systematically by hydrothermal and solvothermal routes. And also to explore the syntheses of rare earth sulfates templated by organic amine hydrothermally.1. Three novel zinc phosphite compounds, 3D [C6H13N2][C6H12N2] [Zn3(H2PO3)(HPO3)3] (1), 2D [C4H12N2]0.5[(CH3)2NH2][Zn2(HPO3)3] (3), 1D [C6H14N2]0.5[Zn(H2PO3)2] (4), have been synthesized in DMF/DOA medium by using DABCO, PIP, N,N-dimethylpiperazine as organic templated agent, respectively:Compound 1 exhibits a 3D chiral open-framework structure with 16-ring channels, which is formed by the distorted {Zn3P4O12} secondary building unit (SBU). The organic amine molecules play dual roles as both ligands and countercations. The bonded DABCO molecule extending from Zn(3) atom occupies the 12-ring. While the free state DABCO molecule resides in the 16-ring channel as countercations balancing the overall negative electrostatic charge of the open-framework structure.Compound 3 exhibits a 2D layered structure with 4- and 12-rings, where diprotonated PIP molecules occupy the middle of 12-ring windows, and monoprotonated dimethylamine molecules (coming from the decompose of DMF) lie in the layers, through the H-bond interacting with the inorganic framework.Compound 4 is the first example of zinc phosphite with 1D neutral chain structure. Non-protonated N,N-dimethylpiperazine molecules through H-bonds interact with the neutral inorganic chain, forming 3D super-molecular structure.2. By changing the kinds of solvent and reaction temperature, we obtain two 3D open-framework structural zinc phosphite compounds, [C6H13N2][C6H12N2][Zn3(H2PO3)(HPO3)3] (1) and [C6H14N2][Zn3(HPO3)4] (2), using DABCO as organic templated agents in the same reaction molar ratio. Compound 1 was obtained in DMF/DOA medium, while compound 2 was obtained in THF/H2O medium. Compound 2 exhibits a 3D open-framework structure with 8-ring channels, which is different from the structure of compound 1. In addition, we study the Influence of DMF/DOA volume ratio to the product 1.3. Using imidazole and its derivative as organic amine, we extend the research to the ZnHPO3-imidazole-H2O system. We have successfully synthesized a series of ZnHPO3-imidazole compounds (compound 5-10): In compound 5-7, imidazole and its derivative all act as the organic ligands. The structures are all build up by {ZnO3N} and {HPO3} basic structural units and Zn/P ratio of 1:1. Compound 5 exhibits a 1D chiral chain, which is the first example of zinc phosphite possessing the hydrogen-bonded helix. Compounds 6 and 7 with the same formula [C5H8N2][Zn(HPO3)] and different structures have been hydrothermally synthesized using 2-ethylimidazole and 1,2-dimethylimidazole as organic ligands, respectively. Compound 6 exhibits 1D chain structure, while compound 7 shows a 2D layer with 4,82-topolgy. Interestingly, there is H-bond interaction between the organic ligands and inorganic chains in compound 6, forming the 2D super-molecular layers. And there is no H-bond interaction in compound 7, the structure is stabilized by the strongπ-π* interactions between the organic ligands, which is extended from 2D layers to 3D super-molecular structure. Compounds 8 and 9 have been hydrothermally synthesized using imidazole and 2-methylimidazole as organic templated agent, respectively.The two compounds have the similar inorganic framework structures, which both exhibit 2D double layer structures with double 12-rings. Due to the different space-filling effect of the guest molecules, the stacking mode of adjacent layers and the arrangement mode of the organic amines are distinct. Compound 10, Na2Zn3(HPO3)4, has been hydrothermally synthesized using 2-ethylimidazole or 2-methylimidazole as organic templated agent. Na+ lies in the channels through the static gravitation interacting with the inorganic framework. Though guest molecules do not enter the inorganic framework, it is absolutely necessary in the formation of the framework. Owing to the similar structure of 2-ethylimidazole or 2-methylimidazole, we can obtain compound 10 in similar reaction condition.4. By using DETA as the organic ligand and the structure-directing agent, a new 2D layer zinc phosphite Zn(DETA)Zn2(HPO3)3 (11) has been hydrothermally synthesized. Its structure consists of ZnO4,ZnO3N2 and HPO3 basic building units. The ZnO4 tetrahedra and HPO3 pseudo pyramids are connected to form an infinite 2D sheet with 4-, 8- and 12-rings. It is interesting that {Zn2O2(DETA)2} dinuclear units are grafted in the 12-rings.5. In FeHPO3-amine-HF-H2O system, a novel 3D fluorinated iron phosphite Fe2(HPO3)F2 (12) has been synthesized using imidazole as organic templated agent. Its structure consists of FeO3F3 and HPO3 structure building units. Interestingly, all the oxygen and fluorin atoms in this framework are tri-bridging atoms. Presence of the -Fe-F-Fe- linkage leading to a 2D layer in the framework is a noteworthy feature. 6. Three novel neodymium sulfate compounds, 2D [C2N2H10]1.5[Nd (SO4)3(H2O)]·2H2O (13), 3D [Nd(SO4)1.5(H2O)2]?0.5H2O (14) and 3D Nd2(SO4)3(H2O)4 (15), have been hydrothermally synthesized by using en and DETA as organic templated agent, respectively. The structures of compounds 13 and 14 both consist of {NdO9} and {SO4} basic structural units. Compound 15 shows 3D framework structure consisting of {NdO9} , {NdO8} and {SO4} basic structural units.
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