Crystal structure of hexa-μ-chlorido-μ(4)-oxido-tetra­kis­{[1-(2-hy­droxy­eth­yl)-2-methyl-5-nitro-1H-imidazole-κN (3)]copper(II)} containing short NO(2)⋯NO(2) contacts

The title tetra­nuclear copper complex, [Cu(4)Cl(6)O(C(6)H(9)N(3)O(3))(4)] or [Cu(4)Cl(6)O­(MET)(4)] [MET is 1-(2-hy­droxy­eth­yl)-2-methyl-5-nitro-1H-imidazole or metronidazole], contains a tetra­hedral arrangement of copper(II) ions. Each copper atom is also linked to the other three copper atoms in the tetra­hedron via bridging chloride ions. A fifth coordination position on each metal atom is occupied by a nitro­gen atom of the monodentate MET ligand. The result is a distorted CuCl(3)NO trigonal–bipyramidal coordination polyhedron with the axial positions occupied by oxygen and nitro­gen atoms. The extended structure displays O—H⋯O hydrogen bonding, as well as unusual short O⋯N inter­actions [2.775 (4) Å] between the nitro groups of adjacent clusters that are oriented perpendicular to each other. The scattering contribution of disordered water and methanol solvent mol­ecules was removed using the SQUEEZE procedure [Spek (2015 ▸). Acta Cryst. C71, 9–16] in PLATON [Spek (2009 ▸). Acta Cryst. D65, 148–155].