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Updated: Jul 10, 2026
High Resolution Physical Characterization of Single Metallic Nanoparticles
Published on: June 28, 2019
Breaking symmetry: spontaneous resolution of a polyoxometalate
Yu Hou1, Xikui Fang, Craig L Hill
1Department of Chemistry, Emory University, 1515 Dickey Drive, Atlanta, GA 30322, USA.
Abstract:
A chiral polyoxometalate [Hf(PW11O39)2]10- (1) has been prepared and structurally characterized. It crystallizes in the chiral space group P2(1)2(1)2, as a conglomerate of two enantiomerically pure crystals in the absence of any chiral source. The absolute configuration of 1 was determined from the Flack parameter by X-ray crystallography. The structure of 1 comprises two lacunary [PW11O39]7- units, each functioning as a tetra-dentate ligand sandwiching an 8-coordinate HfIV centre in a distorted square antiprismatic geometry. Optically active crystals of both enantiomers were spectroscopically distinguishable by means of solid state circular dichroism spectroscopy. This hafnium-substituted polyoxometalate (POM), 1, shows that spontaneous chiral resolution, a rare phenomenon, can be operable in POM systems.
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