Syntheses And Magnetic Properties Of3D-4F Metal Clusters

With the development and progress of science and technology,3d-4f metal complexes are of great interest for researchers, because of its novel structure and unique functional properties. In recent years, successive reports of new3d-4f metal complexes and their magnetic properties result in the rapid expansion of this field. It does not only promote peoples to explore the new synthetic method of the systems, but also gradually understand the relationship between crystal internal structure and the magnetic properties. Herein, as part of our efforts in this context, we have successfully obtained nine complexes （1-9） by the reactions of three ligands （2-（2-hydroxybenzylideneamino）phenol （H2L1）, N-（2-（2-hydroxy-3-methoxybenzylideneamino）cyclohexyl）-2-hydroxybenzamide （H2L2） and2-（（3-（2-hydroxybenzylideneamino）-2-hydroxypropylimino）methyl）phenol （H3L3）） with transition metal ions or lanthanides ions. The complexes were characterized by single crystal X-ray analysis, elemental analysis, IR analysis, and magnetic properties. This thesis could be divided into two parts as following:1. We have successfully obtained a series of complexes based on H2L1, H2L2ligands with lanthanides ions and transition metal ions:three octanuclear RE₃Ni₅complexes1-3, trinuclear DyZn2complex4and trinuclear DyNi2complex5. We researched each molecular structure and magnetic properties of complexes（1-3）and complex4and then studied in detail molecular structure of complex5. The complexe1showing a frequency dependency of the out-of-phase （x"） signals indicates slow relaxation of the magnetization. The complexes2and3indicate the ferromagnetic interactions among the metal ions and antiferromagnetic interaction among the metal ions is operative for complex4.2. We have obtained some complexes based on H2L2and H2L3ligands with transition metal ions:two dinuclear Fe₂complexes6,7and two mononuclear complexes8,9. We studied in detail molecular structure of all complexes and magnetic properties of complexes6,7. The results indicate an overall antiferromagnetic interaction among the metal ions for complex6and complex7.