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A unique Mn2Gd2 tetranuclear compound of p-tert-butylthiacalix[4]arene
Yanfeng Bi1, Yanling Li, Wuping Liao
1State Key Laboratory of Rare earth Resource Utilization, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun 130022, People's Republic of China.
Abstract:
A calixarene complex with tetragonal Mn(II 2Gd(III)2 tetranuclear units was synthesized in solvothermal conditions, where the addition of a small amount of water was crucial for the formation of the target compound. In the structure, two tail-to-tail p-tert-butylthiacalixarenes are located in a C-shaped mode with a dihedral angle of 14.29 degrees but not in the conventional antiparallel arrangement and form a sandwich-like subunit with an in-between Mn2Gd2 unit. Both calixarenes assume similar cone shapes of C2v symmetry but are pinched to different extents. The extended structure is constructed by supramolecular stacking of the sandwich-like units with the interstices filled by the solvent. The magnetic property of the title compound has been examined.
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