Kong Xiang-Jian, Ren Yan-Ping, Long La-Sheng, Zheng Zhiping, Nichol Gary, Huang Rong-Bin, Zheng Lan-Sun
State Key Laboratory of Physical Chemistry of Solid Surface and Department of Chemistry, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, China.
Inorg Chem. 2008 Apr 7;47(7):2728-39. doi: 10.1021/ic702079e. Epub 2008 Mar 7.
Dual shell-like nanoscopic magnetic clusters featuring a polynuclear nickel(II) framework encapsulating that of lanthanide ions (Ln = La, Pr, and Nd) were synthesized using Ni(NO3)(2).6H2O, Ln(NO3)(3).6H2O, and iminodiacetic acid (IDA) under hydrothermal conditions. Structurally established by crystallographic studies, these clusters are La20Ni30(IDA)30(CO3)6(NO3)6(OH)30(H2O)12(6).72H2O (1), Ln20Ni21(C4H5NO4)21(OH)24(C2H2O3)6(C2O4)3(NO3)9(H2O)129.nH2O [C2H2O3 is the alkoxide form of glycolate; Ln = Pr (2), n = 42; Nd (3), n = 50], and {[La4Ni5Na(IDA)5(CO3)(NO3)4(OH)5(H2O)5][CO3].10H2O} infinity (4). Carbonate, oxalate, and glycolate are products of hydrothermal decomposition of IDA. Compositions of these compounds were confirmed by satisfactory elemental analyses. It has been found that the cluster structure is dependent on the identity of the lanthanide ion as well as the starting Ln/Ni/IDA ratio. The cationic cluster of 1 features a core of the Keplerate type with an outer icosidodecahedron of Ni(II) ions encaging a dodecahedral kernel of La(III). Clusters 2 and 3, distinctly different from 1, are isostructural, possessing a core of an outer shell of 21 Ni(II) ions encapsulating an inner shell of 20 Ln(III) ions. Complex 4 is a three-dimensional assembly of cluster building blocks connected by units of Na(NO3)/La(NO3)3; the structure of the building block resembles closely that of 1, with a hydrated La(III) ion internalized in the decanuclear cage being an extra feature. Magnetic studies indicated ferromagnetic interactions in 1, while overall antiferromagnetic interactions were revealed for 2 and 3. The polymeric, three-dimensional cluster network 4 displayed interesting ferrimagnetic interactions.
在水热条件下，使用硝酸镍（II）·6H₂O、硝酸镧系元素（Ln = La、Pr和Nd）·6H₂O以及亚氨基二乙酸（IDA）合成了具有多核镍（II）框架包裹镧系离子（Ln）的双壳状纳米磁性簇。通过晶体学研究确定其结构，这些簇分别为La₂₀Ni₃₀(IDA)₃₀(CO₃)₆(NO₃)₆(OH)₃₀(H₂O)₁₂₆·72H₂O（1）、Ln₂₀Ni₂₁(C₄H₅NO₄)₂₁(OH)₂₄(C₂H₂O₃)₆(C₂O₄)₃(NO₃)₉(H₂O)₁₂₉·nH₂O [C₂H₂O₃是乙醇酸的醇盐形式；Ln = Pr（2），n = 42；Nd（3），n = 50]，以及{[La₄Ni₅Na(IDA)₅(CO₃)(NO₃)₄(OH)₅(H₂O)₅][CO₃]·10H₂O}∞（4）。碳酸盐、草酸盐和乙醇酸盐是IDA水热分解的产物。这些化合物的组成通过令人满意的元素分析得到证实。已发现簇结构取决于镧系离子的种类以及起始的Ln/Ni/IDA比例。1的阳离子簇具有开普勒型核心，外部由镍（II）离子构成的二十面体包裹着镧（III）的十二面体核心。2和3与1明显不同，它们结构相同，具有由21个镍（II）离子构成的外壳包裹着20个镧系（III）离子的内壳的核心。配合物4是由Na(NO₃)/La(NO₃)₃单元连接的簇构建块的三维组装体；构建块的结构与1非常相似，一个水合镧（III）离子内化在十核笼中是一个额外特征。磁性研究表明1中存在铁磁相互作用，而2和3显示出整体反铁磁相互作用。聚合物三维簇网络4表现出有趣的亚铁磁相互作用。
