A {Nb6P2W12}‐Based Hexameric Manganese Cluster with Single‐Molecule Magnet Properties. Issue 49 (23rd October 2015)

• Record Type: Journal Article
• Authors: Zhang, Dongdi; Cao, Fan; Ma, Pengtao; Zhang, Chao; Song, You; Liang, Zhijie; Hu, Xiaojing; Wang, Jingping; Niu, Jingyang
• Is Part Of: Chemistry. Volume 21:Issue 49(2015)
• Page Start: 17683
• Page End: 17690
• Publication Date: 2015-10-23
• Subjects: heterometallic cages -- magnetic properties -- molecular magnetism -- polyoxometalates -- transition metals; Chemistry -- Periodicals; 540
• DOI: 10.1002/chem.201502892
• Languages: English
• ISSNs: 0947-6539

Abstract

Abstract: By deliberately using a metastable polyanion [(NbO2 )6 P2 W12 O56 ] 12− (1 ), which was formed in situ, we have discovered the unprecedented hexameric cluster {Mn15 (Nb6 P2 W12 O62 )6 } (2 ), in which the six polyanions [Nb6 P2 W12 O61 ] 10− are alternately connected by four intriguing trinuclear {Mn III 3 } moieties and four {Mn II } linkers. This discovery is the first in which the phosphoniobotungstate has been made accessible by using transition‐metal ions; furthermore, polyanion2 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 of2 . In addition, magnetic‐susceptibility measurements reveal that each {Mn III 3 } subunit is a separate single‐molecule magnet (SMM). This discovery results from the exploration of the reverse effect of metastable polyanion1 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. Abstract : Turning a disadvantage into an advantage : A facile strategy for the use of {(NbO2 )6 P2 W12 } formed in situ with paramagnetic manganese ions has led to the discovery of the unprecedented hexameric cluster {Mn15 (Nb6 P2 W12 O62 )6 } (see figure), which represents the first phosphoniobotungstate‐based transition‐metal derivative and largest niobotungstate cluster reported to date. In addition, the title compound behaves as a single‐molecule magnet (SMM).