| Because compounds diversified structure characteristics and potential of physical and chemical properties of 3d transition metal coordination clusters(Cluster),which has become a hot spot and frontier in the field of inorganic chemistry.According to the literature and the authors' results in research works,the compound for the most part randomly assembled,that is,through series of simulation experiments and trial and error experiments results.Therefore,research the directional design and building complexes,and explore the complexes assembly mechanism,is one of the major challenges of inorganic chemists.So that you can from the default orientation to construct the target structure of the compound,and then further study of the structure-activity relationship of the compounds and the physical and chemical performance.This is,the author through solvent thermal synthesis conditions,using the two kinds of N/O-heterocycle ligands and 3d metal Zn2+,Co2+ions,successfully constructed a series of molecular clusters.Based on the research in the field of new materials good accumulation,the author also use the same research strategy,through the single crystal technology,electrospray mass spectrometry technology,powder diffraction,SQUID and other conventional means of testing these compounds was studied,the basic properties and chemical properties of solid and liquid at the same time,in addition,we also adopts some new technology of synchrotron radiation light source of EXAFS and strong magnetic field technology of EPR,we have also research compound Co64 electron configuration of the single crystalline state and the assembly mechanism of compound,this would be propitious to find the possible self-assembly mechanism of compound.This paper is divided into three chapters:The first chapter is the introduction;summarizes the development and research progress of complexes.It focuses on developing the some new technology methods for research into 3d metal high-nuclearity cluster,also detailed introduction research background and current situation.And combines that with information about mass spectrometry and single crystal structure of compound,by analysis of single crystal structure is discussed under accurate information is how to parse compounds using electrospray mass spectrometry technology of solid liquid structure-activity information,in this article focuses on the study of using electrospray mass spectrometry technology high nuclear state transition metal clusters in solution under the stability of the complete cluster formula.Puts forward a new method of mass spectrometry technology,which is expounded research strategies of the complexes.Through understanding the structural characteristics and solution behavior of compound structures of the compounds are improved physicochemical properties of modified again.Integrate electrospray mass spectrometry with atomic spectroscopy analysis(EXAFS)study self-assembly mechanism of clusters,provide new strategies and new method.The purpose,directions and significance of the research topics and the research progress of this project also were discussed in more detailIn chapter 2,the use of multidentate chelating ligand 1,10-phenanthroline-2,9-dicarboxylic acid as precursor,the introduction of a strong magnetic anisotropy of bivalent cobalt ions,and successfully build a case of sixty-four nuclear clusters of ring structure characteristics.From the analysis on structure characteristics,cobalt ions is rich in a variety of coordination model,master ligand coordination point and rigid plane and the coordination effect of distortion of carboxylic acid,compound of the nanoscale building played a key role.The sixty-four nuclear cobalt clusters is one of the world's largest cobalt base cluster compound,for the 3d transition metal compound high-nuclearity cluster research provides a good example.In the conventional single crystal diffraction cannot resolve compound structure.We use to get information about solid liquid,looking for the right test method.The Shanghai Synchrotron Radiation Facility(SSRF)of the clusters single crystal structure characterization,in the case of a wavelength of 0.7239A,we get the accurate structural information.We found that the compounds with ring structure characteristics of the nanometer scale and symmetry structure is very low.In this structure,containing the end group(M-L),bridge foundation(M-L-M or ?2-L)and surface bridge foundation(including ?x-L which is the main existence(?3-L),and ?2,?3 oxygen bridge can lead to between complex magnetic cobalt ion exchange action within the cluster,found the triangle and tetrahedron is mutual alternating resistance losses of grid connection.Magnetism and static and dynamic characterization,found that compounds 1 shows two slow magnetic relaxation behavior,on the analysis of the ac magnetic susceptibility peak real component(?')signal peak displacement formula can be used ?=(? Tp/Tp)/?(logf)to measure:it is generally believed ?>0.1 belong to the state,super paramagnetic and ?<0.08 is a typical behavior of spin glass.For compounds 1,fitting the results ?=0.185,0.0131,shows that compound Co64 has super paramagnetic behavior,also have spin glass behavior.we use high resolution electrospray mass spectrometry for the clusters had been used to characterize the behavior of single crystal in solution,we found that the compounds 1 under the effect of ionization mass spectrometry,the intact structure framework,and methoxy bridge in clusters and hydroxyl bridge happens step by step substitution and elimination reactions.Also using mass spectrometry technology process of the formation of clusters made a preliminary study,found that formed in the process of reaction[CoxLx(OH)2]-[CoxLx(CH3O)]-and[CoxLxBr]-(x=1,2,3,4,5,6,7,8)this species is very important to the formation of clusters.We also adopt fine atomic spectroscopy(EXAFS)technology,from single crystalline,mother liquor of the precipitated phase and reaction process were characterized,found that the clusters cobalt ions in the center of the forming process of the first shell N/O the coordination number and the surrounding the number of cobalt ions change rule.The combination of the two methods will be beneficial to build a large cluster with novel structure and special functions,controllable synthesis of multi-core cluster compound for the future provide more theoretical basis.In the third chapter,the use of 3d metal ion Co(?),zinc(?),precursor ligand 2-methylquinolin-8-ol and 2-(hydroxymethyl)quinolin-8-ol on the condition of solvent thermal synthetic three novel structures of cluster base complexes.Compounds 2 and 3 in the process of the synthesis of metal salt in the water of crystallization of cluster building played a key role,in the form of ?2-OH bridge connects clusters,and four ?2-OH bridge formation of the cavity can be used as a carrier of the modification reaction after clusters,and the structure of halogen ion in ZnX2 group has the characteristics of can be replaced.Our solution for such a system of more halogen behavior were characterized and the results showed that compounds in solution states maintain a high level of stability,and weak ligand halogen ions under the condition of mass spectrum also did not leave.This means that within the compound molecular halogen ions and formed a strong hydrogen bonding force between the hydrogen atoms around.Because,the stability of the compound structure,easy to replace and structure of halogen ions loci and structure can modify the characteristics of the cavity,and we can adjusted the structure properties of the compound.,however,we use 3d transition metal ions with high customize state of cobalt ions with 2-methylquinolin-8-ol ligands in the microwave assisted solvent thermal conditions,to build a case of dinuclear cobalt base cluster compound,is unique for each cobalt ions are five between triangular bipyramid and tetrahedron coordination environment,mainly reported the change of the structure of the compounds under the induction of external force and the change of magnetic properties,and mainly by conventional magnetic characterization of EPR and strong magnetic field technology of compound do the tracking. |
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