Precise Molecular Design and Construction of Organic Ferromagnets

1)具有星状结构的超高自旋聚卡宾的合成：合成了一系列聚卡宾1，3，5-[H(C_6H_4C：)n/3]3C_6H_3，从它们的磁化数据中发现，当n=6和n=9时，它们分别具有前所未有的高自旋S=6和9基态。在优化了构建1，3，5-三取代中心苯环的反应条件后，我们合理地将其推广到具有更高自旋浓度的更高支化的聚卡宾。虽然一些聚卡宾由于磁化主轴的旋转被阻断而表现出超顺磁性，但分子间和分支间的相互作用被发现是反铁磁性的。2)持久性高自旋多氮氧自由基的合成：通过铁磁偶联剂m-C_6H_4或1，3，5-C_6H_3将两个或三个氮氧自由基中心组装成一个分子。通过EPR精细结构和SQUID磁化率的分析，发现二氮氧自由基和三氮氧自由基具有三重和四重基态，3)组装高自旋分子构建分子磁体：过渡金属络合物的二价和三价配体均以持久的二氮氧自由基和三氮氧自由基为配体。在Mn(HFAc)_2和三氮氧自由基(TN)的组合情况下，得到了居里温度分别为3.4和46K的分子磁体。X射线结晶学分析揭示了层状蜂窝状网络和三维交叉平行结构，它们分别由(TN)_2{Mn(HfAc)_2}_3单元组成。3.固态有机自由基分子间相互作用的设计与综述：芳香族聚酰胺中氢键相互作用的原型和聚噻吩类化合物中的S-S相互作用，以发现这些相互作用在促进分子间自旋排列方面的潜力。

1) Synthesis of Super-high-spin Polycarbenes with Starburst Structures : A series of polycarbenes 1,3,5- [H (C_6H_4C : ) n/3] 3C_6H_3 have been synthesized and found from their magnetization data to have unprecedentedly high-spin S=6 and 9 ground states for n=6 and 9, respectively. Having optimized the reaction conditions for the construction of the 1,3,5-trisubstituted central benzene rings, we have made logical extension to more highly branched polycarbenes with higher spin concentration. While some of the polycarbenes showed a superparamagnetic properties due to blocking of the rotation of the principal axis of magnetization, the intermolecular and interbranch interactions were found to be antiferromagnetic.2) Synthesis of Persistent High-spin Polynitroxide Radicals : Two or three nitroxide radical centers were assembled into one molecules by means of ferromagnetic couplers m-C_6H_4 or 1,3,5-C_6H_3. The di-and trinitroxide radicals were found by the analysis of their EPR fine structures and SQUID susceptibility to have triplet and quartet ground states, respectively.3) Construction of Molecular Magnets by Assembling High-spin Molecules : The persistent di-and trinitroxide radicals were used as di-and trivalent ligands for transition metal complexes. In the case of a combination of Mn (hfac) _2 and trinitroxide radicals (TN), molecular magnets with Curie temperatures of 3.4 and 46 K have been obtained. X-ray crystallographic analyzes revealed the layred honey-combed network and three dimensional crossed-parallels structures, respectively, both consisting of units (TN) _2 {Mn (hfac) _2} _3.4) Design and Survey of Intemolecular Interaction Assisting Spin Alignment in Organic Free Radicals in Solid State : Prototypes for the hydrogen bonding interaction in aromatic polyamides and the S...S interaction in polythiophenes have been studied to find the potentiality of these interaction in helping intermolecular spin alignment.