Crystal structure of bis-(acetato-κ2O,O')di-aqua-[1-(pyridin-2-yl-methyl-idene-κN)-2-(pyridin-2-yl-κN)hydrazine-κN1]terbium(III) nitrate monohydrate.

In the title compound, [Tb(C2H3O2)2(C11H10N4)(H2O)2]NO3·H2O, the Tb3+ ion is nine-coordinated in a distorted tricapped trigonal-prismatic geometry by the three N atoms of the tridentate 1-(pyridin-2-yl-methyl-idene)-2-(pyridin-2-yl)hydrazine ligand, four carboxyl-ate O atoms of two chelating acetate groups and two O atoms of the coordinating water mol-ecules. The organic hydrazine ligand is disordered over two orientations with a refined occupancy ratio of 0.52 (3):0.48 (3). All bond lengths in the coordination environment of the Tb3+ ion are slightly larger than those observed in the isostructural Y3+ and Er3+ complexes. In the crystal, the complex cations are linked by pairs of O-H⋯O hydrogen bonds into dimers. These dimers, nitrate anions and non-coordinating water mol-ecules are joined by O-H⋯O and N-H⋯O hydrogen bonds into a three-dimensional structure.