Influence of alkaline earth oxides (R = Ca, Sr and Ba) on spectroscopic and dielectric studies of iron doped RO–Na2O–B2O3 glasses

Transparent glasses with the composition 20RO–10Na2O–69B2O3–1Fe2O3 (where R = Ca, Sr and Ba) were prepared by melt quenching technique. The amorphous nature of the glass was confirmed by X-ray diffraction pattern of the sample. Physical parameters and spectroscopic studies such as EPR, optical absorption and FTIR were carried out for the glass samples. Besides dielectric properties i.e. dielectric constant (ε′), and loss (tan δ), a.c. conductivity (σac) in the frequency range 103–106 Hz and the temperature range 30–300 °C in air of the present glasses were also investigated. The dielectric and spectroscopic properties have been analyzed in the light of different oxidation states of iron ions in order to understand the influence of alkaline earth oxides as modifier oxide on the structure and insulating strength/conductivity of glass matrix.