Ligand-directed assembly of trinuclear and one-dimensional heterotrimetallic Cu(II)Ln(III)Fe(III) complexes: unusual antiferromagnetic (CuFeIII)-Fe-II coupling via cyano bridges
Ligand-directed assembly of trinuclear and one-dimensional heterotrimetallic Cu(II)Ln(III)Fe(III) complexes: unusual antiferromagnetic (CuFeIII)-Fe-II coupling via cyano bridges
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三核和一维异质三金属 Cu(II)Ln(III)Fe(III) 配合物的配体定向组装：通过氰基桥的不寻常反铁磁 (CuFeIII)-Fe-II 偶联
DOI：
10.1039/c6nj01887d
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发表时间：
2016
影响因子：
3.3
通讯作者：
Kou Hui-Zhong
中科院分区：
文献类型：
--
作者：
Liu Mei-Jiao;Hu Kong-Qiu;Liu Cai-Ming;Cui Ai-Li;Kou Hui-Zhong
新型异三金属配合物[Cu(valpn)(H2O)Ln(H2O)3Fe(CN)6]·xH2O（配合物1为Ln = Gd，x = 3；配合物2为Ln = Tb，x = 3；配合物3为Ln = Dy，x = 1.75；H2valpn = N,N′-双(3-甲氧基水杨基)-1,3-二氨基丙烷)，{[Cu(Me2valpn)]2Ln(H2O)Fe(CN)6·xH2O·yCH3CN}n（配合物4为Ln = Gd，x = 5，y = 2.5；配合物5为Ln = Tb，x = 4.5，y = 1.5；Ln =配合物 6 为 Dy, x = 5.5, y = 2.5; 配合物 7 为 Ln = Y, x = 6, y = 4; H2Me2valpn = N,N′-双(3-甲氧基水杨基)-2,2-二甲基-1,3-二氨基丙烷)通过 Cu(valpn) (或 Cu(Me2valpn))、Ln3+ 和[Fe(CN)6]3−，摩尔比为 2 : 1 : 1。配合物 1-3 具有 CuLnFe 三核结构，由苯氧桥联的 Cu-Ln 和氰基桥联的 Ln-Fe 部分组成。配合物 4-7 包含苯氧桥联的 Cu2Ln 单元，这些单元通过 [Fe(CN)6]3− 连接形成一维 (1D) 之字形结构。在三核配合物 1-3 中，[Fe(CN)6]3− 阴离子与 Ln3+ 配位，而在配合物 4-7 中它与 Cu2+ 配位。磁性研究表明，Cu(II) 和 Gd(III) 离子之间通过苯氧桥存在铁磁相互作用，而氰基桥则在低自旋 Fe(III) 和 Cu(II) 或 Gd(III) 之间传输反铁磁耦合。配合物 1 和 4 的磁化率拟合得到参数 JCuGd = 2.392 和 2.945 cm−1，JFeGd = -0.341 cm−1 和 JFeCu = -0.378 cm−1。交流磁测量表明，配合物 6 显示出缓慢的磁化弛豫，其能垒为 12.3 K，弛豫时间为 τ0 = 1.65 × 10−6 s，这是单链磁体的典型特征。
New heterotrimetallic complexes [Cu(valpn)(H2O)Ln(H2O)3Fe(CN)6]·xH2O (Ln = Gd, x = 3 for complex 1; Ln = Tb, x = 3 for complex 2; Ln = Dy, x = 1.75 for complex 3; H2valpn = N,N′-bis(3-methoxysalicylidene)-1,3-diaminopropane), {[Cu(Me2valpn)]2Ln(H2O)Fe(CN)6·xH2O·yCH3CN}n (Ln = Gd, x = 5, y = 2.5 for complex 4; Ln = Tb, x = 4.5, y = 1.5 for complex 5; Ln = Dy, x = 5.5, y = 2.5 for complex 6; Ln = Y, x = 6, y = 4 for complex 7; H2Me2valpn = N,N′-bis(3-methoxysalicylidene)-2,2-dimethyl-1,3-diaminopropane) have been synthesised by a reaction of Cu(valpn) (or Cu(Me2valpn)), Ln3+ and [Fe(CN)6]3− in a molar ratio of 2 : 1 : 1. Complexes 1–3 have a CuLnFe trinuclear structure, consisting of phenoxo-bridged Cu–Ln and cyano-bridged Ln–Fe moieties. Complexes 4–7 contain phenoxo-bridged Cu2Ln units that are connected by [Fe(CN)6]3− to form a one-dimensional (1D) zig-zag structure. In the trinuclear complexes 1–3, the [Fe(CN)6]3− anion coordinates to Ln3+, whereas it coordinates to Cu2+ in complexes 4–7. Magnetic studies demonstrate that there exists a ferromagnetic interaction between Cu(II) and Gd(III) ions via the phenoxo bridges, while the cyano-bridges transit antiferromagnetic coupling between low-spin Fe(III) and Cu(II) or Gd(III). The fitting to the magnetic susceptibilities of complexes 1 and 4 gave the parameters of JCuGd = 2.392 and 2.945 cm−1, and JFeGd = −0.341 cm−1 and JFeCu = −0.378 cm−1. The ac magnetic measurements reveal that complex 6 shows slow magnetization relaxation with an energy barrier of 12.3 K and a relaxation time of τ0 = 1.65 × 10−6 s, which is typical of a single-chain magnet.