The cocrystal μ-oxalato-κO,O:O,O-bis-(aqua-(nitrato-κO){[1-(2-pyridyl-κN)eth-ylidene]hydrazine-κN}copper(II)) μ-oxalato-κO,O:O,O-bis-((methanol-κO)(nitrato-κO){[1-(2-pyridyl-κN)eth-ylidene]hydrazine-κN}copper(II)) (1/1).

The title cocrystal, [Cu(2)(C(2)O(4))(NO(3))(2)(C(7)H(9)N(3))(2)(H(2)O)(2)][Cu(2)(C(2)O(4))(NO(3))(2)(C(7)H(9)N(3))(2)(CH(4)O)(2)], is a 1:1 cocrystal of two centrosymmetric Cu(II) complexes with oxalate dianions and Schiff base ligands. In each mol-ecule, the Cu(II) centre is in a distorted octa-hedral cis-CuN(2)O(4) environment, the donor atoms of the N,N'-bidentate Schiff base ligand and the bridging O,O'-bidentate oxalate group lying in the equatorial plane. In one mol-ecule, a monodentate nitrate anion and a water mol-ecule occupy the axial sites, and in the other, a monodentate nitrate anion and a methanol mol-ecule occupy these sites. In the crystal structure, inter-molecular N-H⋯O, O-H⋯O and N-H⋯N hydrogen bonds link the mol-ecules into a network. Weak intra-molecular N-H⋯O inter-actions are also observed.