Structural study, spectroscopic characterization, DFT calculations and electrical properties of manganese (II) organic-inorganic hybrid material (C8H14N2)2[MnCl4(H2O)2]Cl2

Abstract

The new organic-inorganic compound, (C8H14N2)2[MnCl4(H2O)2]Cl2 denoted (1), crystallizes at room temperature in the monoclinic system, P21/c space group. The structure exhibits an alternate organic-inorganic layered stacking along a-axis. The inorganic layers formed by [MnCl4(H2O)2]2− anion and two uncoordinated chlorine anions. The organic layers are made of protonated m-Xylylenediamine (C8H14N2)2+. Crystal cohesion is achieved through NH…Cl and OH…Cl hydrogen bonds building up a three-dimensional network. The functional groups present in the crystal were studied by FTIR. The optical proprieties were investigated by UV-visible spectroscopy study and the electronic properties HOMO and LUMO energies were calculated by TD-DFT. Thermal behavior (DSC, DTA/TGA) was also performed, while the composition of the phase was verified by semi-quantitative analysis (EDX). Hirshfeld surface (3D-HS) analysis and the two-dimensional fingerprint plots (2D-FP) affirms that the structure is dominated by H…Cl/Cl…H and H…H contacts. Electrical analysis of our compound has been investigated using complex impedance spectroscopy (CIS) in frequency and temperature range 3 uHz-20 MHz and 393–443 K, respectively. Impedance spectroscopy studies show that electrical-conductivity is 1.80 10−6 S cm−1 at 443 K and the activation energy is 2.15 eV.