Tris(2,2′-bi-1H-imidazole-κ2 N 3,N 3′)cobalt(II) hydrogen phosphate

The title compound, [Co(C6H6N4)3]HPO4, was synthesized under hydro­thermal conditions. In the cation, the CoII atom is octa­hedrally coordinated by six N atoms from three 2,2′-bi-1H-imidazole ligands [Co—N bond lengths are in the range 2.084 (5)–2.133 (6) A]. Inter­molecular N—H⋯O hydrogen bonds form an extensive hydrogen-bonding network, which links cations and anions into a three-dimensional crystal structure.