Disordered structures, vibrational spectroscopy, thermal behavior, and electrical properties of two new tetrachlorometallates complexes [(CH3CH2CH2)4N]2MIICl4 with MII = Co and Mn.

The two new hybrids single crystals having the general formula [(CH 3 CH 2 CH 2) 4 N] 2 M^IICl 4 with M^II = Co (1) and Mn (2) have been synthetised by the slow evaporation process in aqueous solutions. In this article, these compounds were described by the following characterization techniques: X-rays diffraction, thermal analysis (TGA-TDA), vibrational spectroscopy, nuclear magnetic resonance (NMR), and electrical properties. From the crystallographic study, the crystals (1) and (2) have been disclosed to be crystallized too in the centrosymmetric monoclinic systems, with space group P 2 1 /c (Z = 4) and C 2/c (Z = 8), respectively. Their crystal structures consist of [MCl 4 ²⁻ anions and two different cations [(CH 3 CH 2 CH 2) 4 N]⁺, which are connected by a three dimensional network of C-H···Cl hydrogen bonds. In both crystals, each M^II center atom being surrounded by four chloride ligands forming a slightly distorted tetrahedral geometry. The tetrahedral [CoCl 4 ²⁻ is ordered, while the tetrahedral [MnCl 4 ²⁻ is disordered. Some tetrapropylammonium cations of these compounds are found to be disordered. The thermal analysis studies made in the temperature range (298–473 K) did not show any phase transition for the two crystals. Furthermore, the electrical properties of the two compounds are studied by using the complex impedance spectroscopy technique in the temperature and frequency field varied of 290–363 K and 1 kHz–13 MHz, respectively. [ABSTRACT FROM AUTHOR]