Crystal structure of [Y6(μ6-O)(μ3-OH)8(H2O)24]I8·8H2O
Résumé
The crystal structure of the title compound {systematic name: octa-3-hydroxido-6-oxido-hexakis[tetraaquayttrium(III)] octaiodide octahydrate}, ischaracterized by the presence of the centrosymmetric molecular entity [Y6(6-O)(3-OH)8(H2O)24]8+, in which the six Y3+ cations are arranged octahedrallyaround a 6-O atom at the centre of the cationic complex. Each of the eightfaces of the Y6 octahedron is capped by an 3-OH group in the form of adistorted cube. In the hexanuclear entity, the Y3+ cations are coordinated by thecentral 6-O atom, the O atoms of four 3-OH and of four water molecules. Theresulting coordination sphere of the metal ions is a capped square-antiprism.The crystal packing is quite similar to that of the orthorhombic [Ln6(6-O)(3-OH)8(H2O)24]I88H2O structures with Ln = La—Nd, Eu—Tb, Dy, except thatthe title compound exhibits a slight monoclinic distortion. The proximity of thecationic complexes and the lattice water molecules leads to the formation of athree-dimensional hydrogen-bonded network of medium strength.