Crystal structure of hexa-μ-chlorido-μ<sub>4</sub>-oxido-tetrakis{[1-(2-hydroxyethyl)-2-methyl-5-nitro-1<i>H</i>-imidazole-κ<i>N</i> <sup>3</sup>]copper(II)} containing short NO<sub>2</sub>...NO<sub>2</sub> contacts
Acta crystallographica. Section E, Crystallographic communications