题 目: A {Nb6P2W12}-Based Hexameric Manganese Cluster with Single-Molecule Magnet Properties
作 者: Dongdi Zhang, Fan Cao, Pengtao Ma, Chao Zhang, You Song, Zhijie Liang, Xiaojing Hu, Jingping Wang,* and Jingyang Niu*
刊 名: Chem. Eur. J
年卷页: 2015, 21, 17683-17690
摘 要：By deliberately using a metastable polyanion [(NbO2)6P2W12O56]12- (1), which was formed in situ, we have discovered the unprecedented hexameric cluster {Mn15(Nb6P2W12O62)6} (2), in which the six polyanions [Nb6P2W12O61]10- are alternately connected by four intriguing trinuclear {MnIII3} moieties and four {MnII} linkers. This discovery is the first in which the phosphoniobotungstate has been made accessible by using transition-metal ions; furthermore, polyanion 2 represents the largest niobotungstate cluster reported to date. Analysis by means of electrospray ionization mass spectrometry (ESI-MS) provides insight into the self-assembly process, and the peaks observed relate to the different charge states of the parent cluster, thus confirming the stability of 2. In addition, magnetic-susceptibility measurements reveal that each {MnIII3} subunit is a separate single-molecule magnet (SMM). This discovery results from the exploration of the reverse effect of metastable polyanion 1 possessing high reactivity, thereby turning a disadvantage into an advantage. This finding could define a new synthetic strategy for the design and synthesis of magnetic polyoxometalate (POM) clusters.
