Construction And Characterization Of Bivalent Iron Complexes Based On Tetradentate Nitrogen-containing Ligands

The spin crossover(SCO)phenomenon is a firm example of bistability,therefore,it has great application value in modern life.The construction of new SCO complexes with hysteresis is a major interest in the field of molecular.In this paper,the structure and characterization of divalent iron complexes based on tetradentate ligands were explored.This paper is divided into four chapters:The first chapter is the introduction to definition,development andfeatures of spin crossover complex systems.And I sdescribed the classification and some application of spin crossover complex in details.Finally,I emphasizethe significance and necessity of this thesis.In the second chapter,scheme of complexes 1 and 2 is constructed.And the common and dissimilarities of the two complexes were analyzed from the aspects of structure,IR,magnetism,Mossier spectrum,thermogravimetric analysis,PXRD,DSC,mass spectra and proton conductivity.Actually most of those measurements focus on the transformation from 1 to 2.In the third chapter,Idiscussed the synthesis of new ligands and explored the properties of complexes 4 and 5.And the characteristics of the two complexes were analyzed from the structure,IR,magnetic,thermogravimetric,PXRD and DSC.And It is worth mentioning thatthe scanning rate has an effect on the hysteresis width in the magnetic test.The fourth chapter explains the construction methods of five nuclear complexes 6 and 7.And the characteristics of the two complexes were analyzed from the structure,IR,magnetic,thermogravimetric and PXRD.Most importantly,the effect of iron content on the spin transition was also investigated.