Crystal structure of hydrazine iron(III) phosphate, the first transition metal phosphate containing hydrazine

Abstract

The title compound, poly[(μ2-hydrazine)(μ4-phosphato)iron(III)], [Fe(PO4)(N2H4)]n, was prepared under hydrothermal conditions. Its asymmetric unit contains one FeIIIatom located on an inversion centre, one P atom located on a twofold rotation axis, and two O, one N and two H atoms located on general positions. The FeIIIatom is bound to four O atoms of symmetry-related PO4tetrahedra and to two N atoms of two symmetry-related hydrazine ligands, resulting in a slightly distorted FeO4N2octahedron. The crystal structure consists of a three-dimensional hydrazine/iron phoshate framework whereby each PO4tetrahedron bridges four FeIIIatoms and each hydrazine ligand bridges two FeIIIatoms. The H atoms of the hydrazine ligands are also involved in moderate N—H...O hydrogen bonding with phosphate O atoms. The crystal structure is isotypic with the sulfates [Co(SO4)(N2H4)] and [Mn(SO4)(N2H4)].