Crystal structure of [Y6(μ6-O)(μ3-OH)8(H2O)24]I8·8H2O.

The crystal structure of the title compound {systematic name: octa-μ3-hydroxido-μ6-oxido-hexa-kis-[tetra-aqua-yttrium(III)] octa-iodide octa-hydrate}, is characterized by the presence of the centrosymmetric mol-ecular entity [Y6(μ6-O)(μ3-OH)8(H2O)24](8+), in which the six Y(3+) cations are arranged octa-hedrally around a μ6-O atom at the centre of the cationic complex. Each of the eight faces of the Y6 octa-hedron is capped by an μ3-OH group in the form of a distorted cube. In the hexa-nuclear entity, the Y(3+) cations are coordinated by the central μ6-O atom, the O atoms of four μ3-OH and of four water mol-ecules. The resulting coordination sphere of the metal ions is a capped square-anti-prism. The crystal packing is quite similar to that of the ortho-rhom-bic [Ln 6(μ6-O)(μ3-OH)8(H2O)24]I8·8H2O structures with Ln = La-Nd, Eu-Tb, Dy, except that the title compound exhibits a slight monoclinic distortion. The proximity of the cationic complexes and the lattice water mol-ecules leads to the formation of a three-dimensional hydrogen-bonded network of medium strength.