Electrodynamic characteristics of solid solutions Pb(Fe$_{1-x}$Sc$_{x}$)$_{2/3}$W$_{1/3}$O$_{3}$ in a broad spectral range

The methods of broadband dielectric spectroscopy are used to study the effect of substitution of Fe$^{3+}$ by Sc$^{3+}$ in Pb(Fe$_{1-x}$Sc$_{x}$)$_{2/3}$W$_{1/3}$O$_{3}$ solid solutions of perovskite family on the dielectric response function in the frequency range from 120 Hz up to 100 THz (4 $\times$ 10$^{-9}$–3 $\times$ 10$^3$ cm$^{-1}$). The experimental data are analyzed in the framework of multiparameter dispersion models. The evolution of the dispersion parameters of absorption bands depending on the degree of cation substitution in the $B$ position of perovskite basis of $AB$O$_3$ is discussed.