Crystal structures of isomorphous triaquatris(3-aminobenzoato-O, O)yttrium(III) trihydrate and triaquatris(3-aminobenzoato-0,0)lanthanide(III) trihydrate

Abstract

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(C 7 H 6 NO 2 ) 3 · 3H 2 O] · 3H 2 0 and their crystals are isomorphous in the non-centrosymmetric trigonal space group R 3 c . 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.