On the nature of bulk electrical relaxation in 4-tricyanovinyl-N,N-diethylaniline (TCVA)

Abstract

The AC conductivity, σ(ω,T), of the 4-tricyanovinyl-N,N-diethylaniline (TCVA) in pellets have been studied as a function of frequency and temperature. Analysis of σ(ω,T) shows an excellent agreement of scaling behavior based on the universal power law model. The behavior of σ(ω,T) reveals that the correlated barrier hopping (CBH) model is the predominant conduction mechanism in the bulk TCVA semiconductor material. The activation energies of AC conduction processes were found to decrease with increasing frequency. These results are consistent with the hopping model. Impedance spectroscopy exhibits a single semicircular or part of semicircular arcs at each constant temperature. So, the presence of mutual relaxation behavior within the bulk TCVA. The frequency and temperature dependence of both the dielectric constant ε′(ω) and the dielectric loss ε″(ω) were studied in the frequency and temperature ranges of 10 Hz-5 MHz and 303-373 K, respectively.