Dielectric properties, polarizability and molar refractive index of some VSrFeZnO glasses

The dielectric properties of a set of glasses having the composition (70-x)%V₂O₅ -  x%ZnO - 10%SrO - 20%FeO is studied in terms of their real and imaginary parts of permittivity (ε' and ε") and electric modulus (M' and M"). The dielectric data are collected at the frequencies 120, 10³, 10⁴ and 10⁵ Hz and in the temperature range 300 – 523 K. The electric moduli are treated with Debye, Cole – Cole, Davidson – Cole and Havriliak – Negami equations. Good fitting to the experimental data are obtained with Cole – Cole and Davidson – Cole equations. The static relaxation time τ₀ values are found to vary between 7.6x10^-9 sec and 22.7x10^-9 sec, and the parameters α and γ in the Cole-Cole and Davidson-Cole expressions are found to be (α = 0.056 - 0.065) and (γ = 0.94 - 0.95). The calculated optical basicity values are found to decrease with increasing the %ZnO. The molar refractive index is found to be between 2.6 and 3.2. The calculated single bond strength values suggest the transfer of bond nature from the covalent to the ionic form. The obtained third order nonlinear optical susceptibility χ⁽³⁾ results and electronic polarizability calculations suggests these glasses to be good nominees for nonlinear optical applications.