(H2teta)2{[Ni(teta)][Fe(CN)6]2}•17H2O (teta＝5,7,7,12,14,14-Hexa-methyl-1,4,8,11-tetraazacyclotetradecane)超分子化合物的合成、晶体结构和磁性质研究

将Ni(teta)(ClO₄)₂ (teta＝5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane)的DMF溶液和K₃Fe(CN)₆]的水溶液在填充了琼脂冻胶的U型管中通过扩散反应, 得到了标题化合物(H₂teta)₂{Ni(teta)]Fe(CN)₆]₂}?17H₂O, 该化合物晶体属三斜晶系, 空间群P1, 晶胞参数为a＝0.9998(2) nm, b＝1.5514(3) nm, c＝1.6647(4) nm, α＝114.15(2)°, β＝100.91(2)°, γ＝93.42(2)°, V＝2.2863(10) nm³, z＝1, D_c＝1.196 g?cm^－3, F(000)＝890, μ＝5.84 cm^－1, GOF＝0.894, R₁＝0.0582, wR₂＝0.1446 I＞2σ(I)]. 该化合物的基本单元由2个H₂teta]^2＋阳离子、1个{Ni(teta)]Fe(CN)₆]₂}^4－阴离子和17个水分子组成, 它们之间通过N—H…N氢键而形成具有二维平面结构的超分子化合物. 1.8～300 K变温磁化率研究表明, 化合物中三核体系Fe (s＝1/2)-Ni (s＝1)-Fe (s＝1/2)中心原子间通过氰基桥联而发生强的铁磁相互作用, 磁参数J＝4.33 cm^－1, g＝2.6, θ＝60 K. 通过TG-DTG测定了配合物的热稳定性.

Synthesis, Crystal Structure and Magnetic Property of a Supermolecule (H2teta)2{[Ni(teta)][Fe(CN)6]2}·17H2O(teta= 5,7,7,12,14,14-Hexamethyl- 1,4,8,11 -tetraazacyclotetradecane)

The title compound (H₂teta)₂{Ni(teta)]Fe(CN)₆]₂}?17H₂O was obtained by slow diffusion of an aqueous solution of K₃Fe(CN)₆] and a DMF solu-tion of Ni(teta)](ClO₄)₂ through a U-tube containing agar at room temperature. The compound crystallizes in the triclinic space group P1 with a＝0.9998(2) nm, b＝1.5514(3) nm, c＝1.6647(4) nm, α＝114.15(2)°, β＝100.91(2)°, γ＝93.42(2)°, V＝2.2863(10) nm³, z＝1, D_c＝1.196 g?cm^－3, F(000)＝890, μ＝5.84 cm^－1, GOF＝0.894, R₁＝0.0582, wR₂＝0.1446 I＞2σ(I)]. Its structure con-sists of two cations of H₂teta]^2＋, one trinuclear anion of {Ni(teta)]Fe(CN)₆]₂}^4－ and seventeen water molecules, which are held together by the N—H…N hydrogen bonds to form a two-dimensional supramolecule. The variable temperature magnetic susceptibility, measured in the 1.8～300 K range, indicates the presence of a strong ferromagnetic interaction through the cyanide bridge in trinuclear system Fe (s＝1/2)-Ni (s＝1)-Fe (s＝1/2) with magnetic parameters J＝4.33 cm^－1, g＝2.6, θ＝60 K. The thermal stability of the complex was studied by TG-DTG.