Abstract
The alternating current (AC) conductivity and dielectric properties of the p-N,N dimethylaminobenzylidenemalononitrile (DBM) were investigated in the frequency range from 5 kHz to 2 MHz within the temperature range from 291 to 413 K. The temperature dependence of AC conductivity and the frequency exponent, s, is reasonably well interpreted by the correlated barrier hopping (CBH) model. The activation energy (ΔEAC), the pre-exponential factor (σ0), and the density of states at Fermi level (N(EF)) were determined. The dielectric constant and dielectric loss increase with temperature at low frequencies and are frequency independent at high frequencies.
► DBM compound is of the type donor-phenyl-acceptor (D-ph-A). ► Both capacitance and loss tangent are found to decrease by increasing frequency. ► Both capacitance and loss tangent are found to increase by increasing temperature. ► Single polaron hopping mechanism is the dominating conduction in DBM compound.