Three organically templated magnesium sulfates: Chemical preparation, hydrogen-bonded structures and thermal behavior

Three new organically templated magnesium sulfates using ethylenediamine, dabco and piperazine have been synthesized by the slow evaporation method and structurally characterized by single-crystal X-ray diffraction. The chemical purity of the products and the presence of the different entities building the compounds were tested by the EDAX measurements, chemical analysis of the elements and the IR spectroscopy. Compound (I), (C2H10N2)[Mg(SO4)2(H2O)4], crystallizes in the triclinic system, space group P −1, while both hybrid materials (C4H12N2)[Mg(H2O)6](SO4)2 (II) and (C6H14N2)[Mg(H2O)6](SO4)2 (III) adopt another structure type and they crystallize in the monoclinic system, space group C2/c. The three supramolecular compounds are built from anions and cations linked together through a 3-D hydrogen bond network. The thermal decomposition of precursors, studied by thermogravimetric analysis (TG) and temperature-dependent X-ray diffraction (TDXD), show successive intermediate hydrates and crystalline anhydrous compounds upon dehydration.

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► 3 Organically templated magnesium sulfates were synthesized by the slow evaporation method.
► Compound (I) crystallizes in P −1 space group while the two other crystallize in C2/c.
► The thermal decomposition depends on the crystal structure type and the used amine.