Synthesis, crystal structure and dielectric properties of C6H18N2SbCl5

摘要

The result of the X-ray diffraction, differential scanning calorimetry and dielectric studies on a new crystal material C6H18N2SbCl5 is presented. The new organic-inorganic compound has been synthesized and characterized by the X-ray diffraction method at 296(2) K. It crystallizes in the monoclinic P21 space group. The cell dimensions are: a = 5.8617(1), b = 15.7069(2) angstrom, c = 16.6693(2) angstrom, beta = 97.627(1)degrees and Z = 4. The crystal structure consists of a discrete ionic layer of (C6H18N2)(2+) cations and [SbCl5](2-) anions linked via simple and bifurcated N. H center dot center dot center dot Cl hydrogen bonds. DSC analysis shows that this compound undergoes a phase transition at about (384 +/- 2) K. AC and DC conductivities, complex dielectric permittivity e*(omega) and complex electrical modulus M*(omega) were respectively studied as temperature and frequency functions. The combined data support each other and confirm the existence of a structural phase transition at about 384 K. Moreover, the temperature dependence of the DC conductivity and relaxation frequency followed the Arrhenius relation. The frequency dependence of the real part of the AC conductivity in both phases follows the Jonscher's universal dynamic law: s' total sigma total (omega, T) = sigma'(DC)(T) + A(T).omega(s(T)). The behavior of s(T) with temperature suggests that the hopping over barrier model (CBH) and the small polaron tunneling mechanism (SPTM) prevail in phases I and II, respectively. Copyright (C) 2016 John Wiley & Sons, Ltd.