Two Crystal Modifications of the Cocrystal of 5-(hydroxyimino)-1H-Imidazole-3-Oxide with 3,4-Diaminoglyoxime

Two crystal modifications of the cocrystal of (Z)-4-amino-5-(hydroxyimino)-2,2-dimethyl-2,5-dihydro-1H-imidazole-3-oxide with 3,4-diaminoglyoxime in the 2:1 stoichiometric component ratio are studied by single-crystal XRD. It is established molecules of both modifications demonstrate highly similar geometric parameters. Noncovalent bonding in the crystals of both forms is analyzed comprehensively by constructing Hirshfeld surfaces. It is shown that 1H-imidazole-3-oxide chains are rearranged, the fraction of N–H⋯N interactions is diminished and their character is changed upon the introduction of a water molecule into the structure of one modification, while its calculated density and the coefficient of molecular packing in the crystal are not changed significantly.