氮氧自由基-稀土铒(Ⅲ)配合物的合成、结构和磁性研究

Synthesis,Crystal Structure and Magnetic Properties of a Nitroxide Radical-Er(Ⅲ) Complex

采用甲氧基苯基取代的氮氧自由基2MeONIT与稀土Er(Ⅲ)离子进行配位,得到了1个新的三自旋配合物[Er(hfac)_3(2MeONIT)_2](其中2MeONIT=2-(2′-甲氧基苯基)-4,4,5,5-四甲基咪唑啉-3-氧化-1-氧基自由基,hfac=1,1,1,5,5,5-六氟乙酰丙酮).X-射线单晶衍射结果表明,配合物属三方晶系,P3(2)21空间群,是由1个Er(hfac)_3单元和2个2MeONIT自由基组成的单核三自旋结构.变温磁化率研究表明,配合物中稀土Er(Ⅲ)离子和氮氧自由基2MeONIT之间存在着弱的反铁磁相互作用.

A new tri-spin complex of [Er （hfac）3 （2MeONIT）.2] （2MeONIT = 2-（2＇- methoxyphenyl ）- 4, 4, 5, 5-tetramethylimidazoline-1-oxyl, hfac = 1,1, 1,5, 5, 5-hexafluoro- acetylaceonate） was synthesized using a methoxyphenyl substituted nitroxide radical. The single crystal X-ray analysis reveals that the complex crystallizes in trigonal system, space group P3（2）21, and consists of one Er（hfac）3 unit and two 2MeONIT radicals. The variable magnetic measurement shows that there exists weak antiferromagnetic interaction between Er（ III） ion and nitroxide radicals 2MeONIT.