Electrical conductivity, dielectric permittivity and thermal properties of the compound aqua[bis(2-dimethyldminomethyl-4-NIT-phenolato)] copper(II) including NaCl impurity

Abstract

The AC and DC conductivity, the dielectric permittivity and the thermal properties of the compound aqua[bis(2-dimethylaminomethyl-4-NIT-phenolato)] copper(II) including NaCl impurity were investigated. The AC conductivity follows a power law of the frequency sigma(omega)) proportional to omega(s). At high frequency, where s is dependent of temperature, the conduction mechanism is reasonably well interpreted in terms of the correlated barrier hopping model. The DC conductivity indicates classical semiconductor behavior. So, it is evaluated that the sample is a typical inorganic semiconductor as its conductivity increases with increasing temperature and the electronic parameters such as activation energy and room-temperature conductivity are in the regime of semiconductors. It is also found that the dielectric constant and the dielectric loss values decrease with frequency and increase with temperature. The thermal properties were investigated under non-isothermal conditions by thermogravimetry (TGA) and differential scanning calorimetry (DSC). The kinetic parameters such as the order of the reaction, the activation energy (E), enthalpy of formation (DeltaH) and characteristic temperatures of the exothermic peak were determined by means of the TGA and DSC techniques. The thermal conductivity shows enhancement with increasing temperature and, in the thermal conductivity mechanism, dominates transport of electrons. (C) 2003 Elsevier Science B.V. All rights reserved.