Chiral 3d/3d-4f Metal Cluster Compounds Synthesis,Structure And Ferroelectric Properties

Chiral metal cluster complexes,with the double advantages both of chiral complexes and cluster compounds,are a potential molecule-based ferroelectric material.Herein,it has become a research hotspot of reasonable design and synthesis of chiral metal cluster complexes in the field of coordination chemistry.In this thesis,fourteen chiral metal clusters(3d/3d-4f)with novel structure,have been synthesized by the reactions of chiral Schiff base,which possesses abundant coordination sites and various coordination modes,and transition metal ions or rare metal ions.Meanwhile,their crystal structures were characterized and properties were researched in detail.The main content is described following three aspects:First,two pair of chiral tetra-nuclear enantiomer clusters(1?2)and trinuclear enantiomer clusters(3?4)with fluorescence properties and ferroelectric properties,were attained through self-assembling of chiral Schiff base R/S-H2L1 and R/S-HL2 with transition metal zinc salts,respectively.It is worth noting that both of complexes 3 and 4 exhibit great ferroelectric property under the high temperature of 503K,which is the first case with the character of high temperature ferroelectric zinc clusters.Second,a pair of chiral trinuclear enantiomer dissimilar metal clusters(5?6),which possess the fluorescence,dielectric and high temperature ferroelectric properties,were obtained by the reaction of a couple of chiral enantiomer ligands R/S-H2L1 with transition metal zinc salts and rare-earth metal dysprosium salts.The complexes of 5 and 6 display brilliant ferroelectric properties at 413K and 453K,separately.And they are the extremely rare multifunctional high temperature molecular ferroelectric.Third,a series of chiral trinuclear enantiomer different metal clusters(7-14)were constructed through utilizing a pair of chiral enantiomer ligands R/S-HL2 with transition metal zinc salts and different rare-earth metals.All of the complexes(7-14)demonstrate the better ferroelectric properties at the high temperature of 453K.What's more,they also have other properties:the complexes of 7 and 8 show blue-fluorescence,the complex of 9 and 10 respectively has the characteristic fluorescence of Sm3+ and are the rare white-light materials,and Complexes 11-14 display near-infrared luminescent properties.