Redetermination of [Gd(NO3)(3)(H2O) 4]center dot 2H(2)O

The crystal structure of the title compound, tetraaquatris(nitrato-(KO)-O-2, O') gadolinium(III) dihydrate, was redetermined from single-crystal X-ray data. In comparison with the first determination [Ma et al. (1991). Wuji Huaxue Xuebao, 7, 351-353], all H atoms could be located, accompanied with higher accuracy and precision. The Gd III atom shows a ten-coordination with three nitrate ligands behaving in a bidentate manner and the other positions being occupied by four water molecules, forming a distorted bicapped square antiprism. Two nitrate ions coordinate to the metal atom with similar bond lengths while the third shows a more asymmetric bonding behaviour. An intricate network of O-H center dot center dot center dot O hydrogen bonds, including the lattice water molecules, stabilizes the crystal packing.