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

The Ni atom in the title complex, [Ni(SO4)(C15H13N5)(H2O)]·H2O, has a distorted trigonal-bipyramidal coordination formed by the tridentate 2,6-bis(2-pyridylamino)pyridine (tpdaH2) ligand, one sulfate and one coordinated water molecule. The tpdaH2 ligand is three-coordinated, with the N atom of the central pyridine ring in the equatorial position [Ni—N = 1.9961 (14) ] and the N atoms of the peripheral pyridine rings in the axial positions [Ni—N = 1.9668 (15) and 1.9895 (15) ]. 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 tpdaH2 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.