Polyoxometalates: Fascinating structures, unique magnetic properties

We report on several discrete molecular transition metal- and lanthanide-containing polyoxo-tungstates and -molybdates with a focus on their magnetic properties. The polyanions discus sed here all contain 3d paramagnetic centers and are mostly of the spherical {Mo-132} Keplerate type, the cyclic {P8W48} type, the dimeric {(X2W18)-W-III} (X = As, Sb) type, and the dimeric, fused {Si2W18} type. The number of incorporated magnetic ions in the structures described here ranges from 3 to 30. (C) 2009 Elsevier B.V. All rights reserved.