Synthesis And Crystal Structures Of A Few Complexes Of Heavy Alkli Metals Rubidium And Cesium

Being rare and dispersive, the heavy alkli metals rubidium and cesium are less investigated domestically and abroad. Rubidium and cesium compounds we know now are mainly their simple Inorganic compounds or a few organic carboxylates and so on. In recent years, with the continuous development of technology, the properties and applications of rubidium and cesium are paid increasing attention. As we come to understand the applications, physiological and complexity functions of rubidium and cesium, we've realized the importance of of them and their complexes. Since crystal structures are closely related to properties and applications, synthesis and crystal structural analysis of new rubidium and cesium complexes have dramatic significance. In the first part of this dissertatian, the basic knowledge of analytical methods, applications, physiological functions and complexity function of rubidium and cesium are introduced and reviewed.In the second part of this dissertation, ten new rubidium or cesium complexes were synthesized through neutralization reactions using weak acids as ligands. The ten complexes include rubidium 4-nitrobenzoate dihydrate, cesium 4-nitrobenzoate dihydrate, rubidium hydrogen bis(3,5-dinitrobenzoate), rubidium 2,4-dihydroxybenzoate monohydrate, rubidium hydrogen bis(anthranilate), cesium 5-nitropyridin-2-olate, rubidium 5-nitropyridin-2-olate dihydrate and a macrocyclic crown ether complex [Cs(DB24C8)][CuBr2]. All these complexes were characterized by elemental analysis, FT-IR spectroscopy, Raman spectroscopy andⅩ-ray single crystal diffraction. It was found that neither the rubidium cation nor the cesium cation has fixed coordinate number. Bond lengths between the cations and the coordinate atoms, coordinate number of the cations and the shapes of the coordination spheres all change according to the ligands selected. Most of the complexes have sandwich structures. The organization of all layer structures appears to be governed mainly by steric effects and electrostatic forces, and the lattices were mainly stabilized by aromatic packing and intermolecular interactions.In the third part, triazoles and tetrazoles with active hydrogen atoms were selected as lingands and rubidium hydrogen bis(benzotrazolate) dihydrate, cesium hydrogen bis(1-methyl-lH-1,2,3,4-tetrazole-5-thiolate), rubidium 5-aminotetrazol-1-ide and 5-phenyltetrazol-1-ide were synthesized with their single crystals nurtured. Considering the limitation of investigations on alkli metal azolates, their limited amount and relative data, we synthesized potassium hydrogen bis(benzotriazlate), sodium 1-methyl-1H-1,2,3,4-tetrazo1-5-thiolate trihydrate, potassium 1-methy1-1H -1,2,3,4-tetrazol-5-thiolate for convenience for comparison. All seven complexes were characterized by elemental analysis, FT-IR spectroscopy, Raman spectroscopy andⅩ-ray single-crystal diffraction, as well. Through comparison, it was found that sodium cations tend to have regular coordinate numbers and coordinate geometry; coordinate style of potassium cations tend to vary, while rubidium and cesium cations tend to be more variable in coordination and have no fixed coordinate geometry and coordinate number. Generally, the coordinate numbers tend to increase as the radii of the central metal cations increase.In addition, we investigated the topologies of the crystal structures and found some ladder-like fragments constructed byμ3-,μ4-bridging donor atoms or ligands with special structures. 4~4 topological layers, two types of 6~3 topological layers and rare 4~36~3 topological layers were also found.In this dissertation, weak acidic organic ligands were selected to synthesize rubidium and cesium complexes. A few sodium and potassium complexes were synthesized as well. Single crystals of all complexes werenurtured and all of them were characterized by FT-IR spectroscopy, Raman spectroscopy andⅩ-ray single-crystal diffraction. The crystal structures were topological analyzied, as well.