CRYSTAL-STRUCTURES OF ISOMORPHOUS TRIAQUATRIS(3-AMINOBENZOATO-O,O)YTTRIUM(III) TRIHYDRATE AND TRIAQUATRIS(3-AMINOBENZOATO-O,O)LANTHANIDE(III) TRIHYDRATE

The space group and unit cell parameters of yttrium(III) and lanthanide(III) 3-aminobenzoate hexahydrate crystals have been determined. All compounds have the formula [M(C7H6NO2)3.3H2O].3H2O and their crystals are isomorphous in the non-centrosymmetric trigonal space group R3c. Crystal structures of three of these salts have been determined: Y(III), Er(III) and Lu(III). The structures consist of the metal cation coordinated by water molecules, bidentate chelating 3-aminobenzoate anions, and crystallization water. The metal coordination polyhedron, with crystallographically imposed threefold symmetry axis, is formed by nine oxygen atoms: six of carboxylate groups and three of water molecules. The crystal structure is stabilized by interligand hydrogen bonding between water molecules and either carboxylate or amino groups.