Preparation, molecular structure, thermal properties, electrical conductivity analysis and dielectric relaxation of a new hybrid compound (NH2C5H3ClNH)2ZnBr4·H2O

Abstract

Preparation, structural elucidation, Hirshfeld surface analysis, thermal analysis and impedance spectroscopy study are carried out for an interesting organic–inorganic hybrid compound (NH2C5H3ClNH)2ZnBr4·H2O. X-ray diffraction analysis reveals that the title compound belongs to the triclinic crystallographic system with the space group P-1 with Z = 2 and the following unit cell dimensions: a = 7.3209(9) A, b = 8.4407(10) A, c = 16.923(2) A, α(°) = 82.975(6), β(°) = 85.118(6) and γ(°) = 74.398(6). The crystal structure is composed of two protonated 4-amino-2-chloropyridinium cations, tetrabromozincate anions and a water molecule which are held together by a number of hydrogen bonds forming infinite chains. In addition, crystal structure is stabilized with π…π interactions (Cg–Cg and Zn-Cl…Cg, with Cg is the 4-amino-2-chloropyridinium rings) which have also been investigated in terms of their corresponding Hirshfeld surface and the breakdown of fingerprint. To quantify intermolecular interactions in crystal lattice, FT-IR spectroscopy has been used to distinguish the different chemical functional groups and their environments in this molecule. The dielectric conductivity of this compound has been measured in the temperature range 298–438 K and the frequency range 209 Hz–5 MHz. The analysis of the experimental data of the impedance spectroscopy based on the activation energy shows that this material is an ionic–protonic conductor at low temperature and becomes an electronic one at high temperature. This work aims to reveal the thermal properties of a new zinc (II) based organic–inorganic hybrid and the conductivity properties that this compound exhibits.