新型氰基桥联二维配位聚合物{[Fe(salen)]_2[Ni(CN)_4]}_n的合成、晶体结构和磁性质

将Fe(salen)NO_3]的甲醇溶液和K_2Ni(CN)_4]·H_2O水溶液通过H管扩散反 应,得到了一个新型氰基桥联配位聚合物{Fe(salen)]_2Ni(CN)_4]}_n (H_2salen为N,N'-二水杨醛缩乙二胺席夫碱)。该化合物属四方晶系。空间群 P4/ncc,晶胞参数为a=b=1.4216(2)nm, c=1.7471(5)nm, V=3.5308(12)nm~3,Z=.该 配合物通过Ni-CN-Fe(salen)-NC-Ni链连接形成二维枕形网格结构,其中键长Ni-C 0.1876(3)nm, Fe-N 0.2170(3) nm, 键角Fe-N-C 164.9(3)°,Ni-C-N 178.9(4) °;金属中心Ni(III)和Fe(III)分别具有正方形和畸形变八面体配位构型。变温磁 化率研究表明,配合物存在分子内反铁磁相互作用,其Fe(III)…Fe(III)交换积分 为-0.041cm~(-1).

Synthesis, Crystal Structure and Magnetic Properties of a Cyano- bridged Two-dimensional Coordination Polymer {[Fe(salen)]_2[Ni(CN)_4] }_n

A cyano-bridged coordination polymer, j Fe (salen)]_2 Ni ( CN)_4] }_n ( salen = N, N'-ethylenebis-(salicylideneimi-nato)-dianion), prepared by slow diffusion of an aqueous solution of K2Ni(CN)4]· H_2O and a MeOH solution of Fe(salen)-NO3] in an H tube, has been characterized by X-ray structure analysis, IR spectra and magnetic measurements. The complex crystallizes in the tetragonal space group PA/ncc with a = b = 1.4216(2) nm, c= 1.7471(5) nm, V = 3.5308(12) nm~3, Z = 4. The product assumes a two-dimensional network structure consisting of pillow-like octanuclear -Ni-CN-Fe(salen)-NC-_]4 units with dimensions: Ni-C = 0.1876(3) nm, Fe-N = 0.2170(3) nm, Fe-N- C= 164.9(3)°, Ni-C-N= 178.9(4)°. The two metal atoms Ni( II )and Fe( HI) have square and slightly distorted octahedral arrangements, respectively. The variable temperature magnetic susceptibility, measured in the 5 ～ 300 K range, indicates the presence of a weak intralayer antiferromagnetic interaction and gives an Fe( III) …Fe (III) exchange integral of - 0.041 cm"