| The design and synthesis of coordination polymers with novel structures and excellent properties have been diffusely researched in the field of coordination chemistry and crystal engineering, mainly because of their advantages and potential applications as functional materials for the past few years. The dissertation is aimed at constructing transition and lanthanide compounds which possess favorable luminescence and magnetic properties, as well as good thermostability. Three series, forty-five transition and/or lanthanide compounds are successfully designed and synthesized under hydrothermal conditions by the reactions of three kinds of bifunctional carboxylic derivatives of terpyridine with transition metal (Zn?, Cd?, Co?) and/or lanthanide ions (Pr?, Nd?, Sm?, Eu?, Gd?, Tb?, Dy?, Ho?, Er?, Yb?). These compounds are characterized by X-ray single crystal diffraction, IR spectra and elemental analyses. Their luminescence and magnetic properties have been investigated, as well as their thermal stabilities. The dissertation includes four chapters as follows:Chapter 1:The application and research actuality of coordination polymer were systematically presented. Reviews on research development of derivatives of terpyridine were also briefly summarized.Chapter 2:The ligand 4'-(2-carboxyphenyl)-4,2':6',4"-terpyridine (HL1) has been synthesized according to the modified method. Eleven diverse transition metal (Zn?, Cd?, Co?) compounds (1-11) based on HL1 and aliphatic/aromatic carboxylic acid as auxiliary ligands have been synthesized successfully. Meanwhile, sixteen lanthanide compounds have also been obtained via the reaction of HL1 and Pr?,Nd?, Sm?, Eu?, Gd?, Tb?, Dy?, Ho?, Er?, Yb? in the presence of auxiliary ligand. The effects of reaction conditions and auxiliary ligands on structures have been discussed. The results indicate that many external factors can regulate and control the assembly process of coordination polymer to some extent, such as anions of the metal salts, auxiliary ligands, pH values, and reaction temperature. The luminescence properties of compounds 1-8 and 12-27 have been studied, and the results show that compounds 1-8 possess good luminescence properties and nanosecond range of lifetime. Moreover, HL1 is able to sensitize the luminescence of Eu? and Tb? effectively. Based on that, a series of Eu?-doped Tb? compounds were designed by adjusting the stoichiometric ratio of Eu? and Tb? in order to obtain white-light emission. In addition, magnetic studies of compounds 9-11 reveal that compound 9 is an SMM (Single molecule magnet), while 10 and 11 both exhibit antiferromagnetic behavior. Thermal stabilities of compounds 1-27 have also been studied.Chapter 3:The ligand 4'-(3-carboxyphenyl)-4,2':6',4"-terpyridine (HL2) has been designed and synthesized. With the introduction of aliphatic/aromatic carboxylic acid as auxiliary ligands, three transition metal (Zn?, Cd?) compounds (28-30) stemming from HL2 have been hydrothermally synthesized at the temperature of 180?, while ten lanthanide (Pr?, Nd?, Sm?, Eu?) compounds (31-40) have been constructed at the temperature of 160?. The effects of the location of functional groups in the ligand and the coordination orientation of auxiliary ligands on the structural dimension of compounds have been discussed. At the same time, the exact conditions of constructing coordination polymers in this series have been confirmed through experimental exploration. Additionally, the luminescence properties and thermal stabilities of compounds 28-40 have also been investigated.Chapter 4:The ligand 4'-(3-carboxyphenyl)-2,2':6',2"-terpyridine (HL3) has been designed and synthesized according to similar procedure as that of HL2. Five transition metal (Zn?, Cd?) compounds (41-45) have been synthesized from HL3 and auxiliary ligands (aliphatic/aromatic carboxylic acid) under hydrothermal conditions. The effects of the position of coordination sites in the ligand and the introduction of auxiliary ligands on the construction of compounds have been discussed. Besides, the luminescence properties and thermal stabilities of compounds 41-45 have also been investigated. |
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