In the field of commercialization, lead-free metal halide perovskite materials are becoming more popular these days because of their prospective use in solar cells and also in other optoelectronic applications. In this paper, a non-toxic CsSnCl₃ metal halide is successfully synthesized via the slow evaporation solution growth technique. Such systematic characterizations as differential scanning calorimetry (DSC) measurements, dielectric measurements, and variable-temperature structural analyses indicate that CsSnCl₃ goes through a reversible phase transformation at T = 391/393 K from the monoclinic to the cubic system. Optical measurements of CsSnCl₃ reveal a direct band-gap value of about 3.04 eV. The study of the charge transfer mechanism of CsSnCl₃ is carried out based on Elliott's theory. The conduction mechanism in CsSnCl₃ is interpreted through the following two approaches: the non-overlapping small polaron tunneling (NSPT) model (monoclinic phase) and the overlapping large polaron tunneling (OLPT) model (cubic phase). Moreover, the high dielectric constant of CsSnCl₃ which is associated with a low dielectric loss makes it a possible candidate for energy harvesting devices.

[N(CH₃)₃H]₂ZnCl₄ has been studied by X-ray powder diffraction patterns, differential scanning calorimetry (DSC), and impedance spectroscopy. The [N(CH₃)₃H]₂ZnCl₄ hybrid compound is crystallized at room temperature (T $\approx$ 300 K) in the orthorhombic system with Pnma space group. Five phase transitions (T₁ = 255 K, T₂ = 282 K, T₃ = 302 K, T₄ = 320 K, and T₅ = 346 K) have been proved by DSC measurements. The electrical technique was measured in the 10⁻¹-10⁷ Hz frequency range and 233–363 K temperature interval. The frequency dependence of alternative current (AC) conductivity is interpreted in terms of Jonscher's law. The AC electrical conduction in [N(CH₃)₃H]₂ZnCl₄ is analyzed by different processes, which can be attributed to several models: the correlated barrier hopping model in phase I, the overlapping large polaron tunneling model in phase II, the quantum mechanical tunneling model in phase IV, and the non-overlapping small polaron tunneling model in phases III, V, and VI. The conduction mechanism is studied with the help of Elliot's theory, and the Elliot's parameters are determined.

[N(CH₃)₃H]₂ZnCl₄ has been analyzed by X-ray powder diffraction patterns, differential scanning calorimetry and impedance spectroscopy. The [N(CH₃)₃H]₂ZnCl₄ hybrid compound is obtained by slow evaporation at room temperature and found to crystallize in the orthorhombic system with Pnma space group. Five-phase transitions at low temperature were detected by differential scanning calorimetry measurements. The analysis of Nyquist plots has revealed the contribution of three electrically active regions corresponding to the bulk mechanism, distribution of grain boundaries and electrode processes. The dielectric relaxation is described by a non-Debye model. The study of the dielectric constants ϵ′, ϵ″ and loss tangent tan (δ) with frequency exhibits a distribution of relaxation times. The complex modulus plots have confirmed the presence of grains and grain boundaries as well as a non-Debye type of relaxation in the material. Thermodynamic parameters such as the free energy for dipole relaxation ΔF, the enthalpy ΔH and the change in entropy ΔS have been determined with the help of the Eyring theory.

The [N(CH₃)₃H]₂CuCl₄ single crystal has been analyzed by X-ray powder diffraction patterns, differential scanning calorimetry (DSC), and electrical impedance spectroscopy. [N(CH₃)₃H]₂CuCl₄ crystallizes at room temperature in the monoclinic system with P2₁/_C space group. Three phase transitions at T₁ = 226 K, T₂ = 264 K, and T₃ = 297 K have been evidenced by DSC measurements. The electrical technique was measured in the 10⁻¹–10⁷ Hz frequency range and 203–313 K temperature intervals. The frequency dependence of alternative current (AC) conductivity is interpreted in terms of Jonscher's law (developed). The AC electrical conduction in [N(CH₃)₃H]₂CuCl₄ compound is studied by two processes which can be attributed to a hopping transport mechanism: the correlated barrier hopping model in phases I, II, and III, the non-overlapping small polaron tunneling model in phase IV. The conduction mechanism is interpreted with the help of Elliot's theory, and the Elliot's parameters are found.