Aqua[2,6-bis(2-pyridylamino)pyridine]-sulfatonickel(II) monohydrate

The Ni atom in the title complex, [Ni(SO4)(C15H13N5)(H2O)]center dot H2O, has a distorted trigonal-bipyramidal coordination formed by the tridentate 2,6-bis(2-pyridylamino) pyridine (tpdaH(2)) ligand, one sulfate and one coordinated water molecule. The tpdaH(2) ligand is three-coordinated, with the N atom of the central pyridine ring in the equatorial position [Ni-N = 1.9961 (14) angstrom] and the N atoms of the peripheral pyridine rings in the axial positions [Ni-N = 1.9668 (15) and 1.9895 (15) angstrom]. The remaining equatorial positions are occupied by the O atoms of the sulfate ligand and the water molecule. The H atoms of both NH groups of the tpdaH(2) ligand are involved in hydrogen bonds with the O atoms of the uncoordinated water molecule and the sulfate group which link the complex molecules, forming an infinite three-dimensional network.