The synthesis of two new Hofmann-type M(3-aminopyridine)(2)Ni(CN)(4) [M = Zn(II) and Cd(II)] complexes and the characterization of their crystal structure by various spectroscopic methods

The aim of this work is to obtain new examples of Hofmann-type complexes in single crystal form. Two novel Hofmann-type Zn(3-aminopyridine)(2)Ni(CN)(4) (1) and Cd(3-aminopyridine)(2)Ni(CN)(4) (2) complexes in a single crystal form have been synthesized and characterized by elemental, thermal and vibrational (FT-IR and FT-Raman) analysis. The general information about the structural properties of these Hofmann-type complexes 1 and 2 was acquired from the FT-IR and FT-Raman spectra by considering changes at characteristic peaks of the cyano group and 3-aminopyridine ligand molecule. The thermal behaviors of these Hofmann-type complexes 1 and 2 have also been investigated in the range of (50 600) degrees C using the TG and DTG methods. Also, the magnetic susceptibility measurements of these Hofmann-type complexes 1 and 2 were made at the room temperature using the Gouy-balance. The properties of the structure of the Hofmann-type complexes 1 and 2 have been determined by the single crystal diffraction technique. The asymmetric units of the Hofmann-type complexes 1 and 2 contain one M(II) ion [M = Zn(II) in the crystal 1 and Cd(II) in the crystal 21, one Ni(II) ion, one 3-aminopyridine ligand, and one cyanide ligand. The most important feature of the Hofmann-type complexes 1 and 2 is the presence of obvious intermolecular C-H center dot center dot center dot Ni interactions between Ni(II) ion and H atom of the 3-aminopyridine ligand molecule. All spectral and thermal data also support the crystal structures of the Hofmann-type complexes 1 and 2. These newly obtained Hofmann-type complexes 1 and 2 can be used to imprison certain molecules suitable for the gaps in their structure or to separate certain sized molecules one from another as molecular sieves. (C) 2018 Elsevier B.V. All rights reserved.