Synthesis, crystal structures, Hirshfeld surface analysis and physico-chemical characterization of two new ZnII and CdII halidometallates

Abstract

Two new organic–inorganic hybrid materials, based on 1,3-CycloHexaneBis-(Methyl Amine), abbreviated CHBMA, namely (H2CHBMA)ZnCl4·2H2O (CP1) and (H2CHBMA)CdI4·2H2O (CP2), have been synthesized under mild conditions in acidic media and characterized by single-crystal X-ray diffraction, spectroscopic techniques (13C NMR, FTIR, RAMAN) and thermal analysis. The crystal structures of the two compounds were solved by single-crystal X-ray diffraction methods. Both compounds show a 3-dimensional supramolecular structure directed by various interactions between tetrahalidometallate anions (ZnCl42−, CdI42−), water molecule and organic cations (H2CHBMA)2+. For both compounds, the cyclohexane ring of the template cation is in a chair conformation with the methylammonium substituent in the equatorial positions and the two terminal ammonium groups in a cis conformation but with two different orientations (upward for CP1 and downward for CP2) which influences the supramolecular architecture of the two structures. Hirshfeld surface analysis and the associated two-dimensional finger print plots were used to explore and quantify the intermolecular interactions in the crystals.