Design of One-Dimensional Coordination Networks from a Macrocyclic {3d-4f} Single-Molecule Magnet Precursor Linked by [W(CN)8]3– Anions

• Published in: Inorganic chemistry 2013-12, Vol.52 (23), p.13685-13691
• Main Authors: Dhers, Sébastien, Feltham, Humphrey L. C, Clérac, Rodolphe, Brooker, Sally
• Format: Article
• Language: English
• Subjects: Chemical Sciences; Material chemistry
• ISSN: 0020-1669; 1520-510X
• DOI: 10.1021/ic402248y

The outcome of 1:1 reactions of the tetranuclear 3d-4f Single Molecule Magnet (SMM) [Cu3Tb(LPr)(NO3)2(H2O)]NO3 (1) with (TBA)3[W(CN)8] (TBA = tri-n-butyl ammonium cation, [(n-Bu)3N–H]+) in dimethylformamide (DMF) is dependent on the crystallization method employed: liquid–liquid diffusion of the reagents together gives {[Cu3Tb(LPr)W(CN)8(DMF)4]·(DMF)} n (2) whereas diethyl ether vapor diffusion into the reaction solution gives {[Cu3Tb(LPr)W(CN)8(DMF)3(H2O)3]·(DMF)1.5·(H2O)0.5} n (3). Both compounds are obtained as black single crystals and feature one-dimensional (1D) coordination networks (chains) of [1]3+ macrocycles linked by [W(CN)8]3– anions. The two assemblies differ from a structural point of view. Complex 2 has a stepped arrangement with the linkers bound to the opposite faces of the macrocycle, whereas 3 has a square-wave arrangement due to the linkers binding to the same face of the macrocycle. Both compounds display an antiferromagnetic ground state below 3.5 and 2.4 K with a metamagnetic and antiferromagnetic (T, H) phase diagram for 2 and 3, respectively. Remarkably the slow dynamics of the magnetization of the [1]3+ macrocycle units is preserved in 3 while this property is quenched in 2 because of stronger intra- and interchain magnetic interactions inducing a higher critical temperature.