The SiO2-doped with Sm3+ of various concentrations (100-x) SiO2:xSmO3/2 (where x = 0.5, 1.0, 1.5, 2.0 mol%) have been prepared by sol–gel method and non-linearity was studied. The physical parameters like density, molar volume, total molecular weight, refractive index, reflection loss, molar refractivity, energy gap, molar electronic polarizability, dielectric constant, optical dielectric constant, electronic polarizability, ionic concentration, polaron radius, inter ionic distance, field strength and optical basicity were obtained. The structural information was acquired through Fourier transform infrared (FTIR). On the basis of the measured values of the density and refractive index, the Sm3+ ion concentration in glasses, the polarizability of oxide ions and optical basicity were found to increases with rare earth (RE) ions concentration. Theoretically the oxide ion polarizability increases with the refractive index and decrease with energy gap. The theoretical value of molar refraction, electronic polarizability, oxide ion polarizability and metallization criterion were calculated by using Lorentz-Lorenz equation. Theoretical optical basicity of the glasses is evaluated based on equation proposed by Duffy and Ingram. The dielectric constant and optical dielectric constant were found to increase with increase in RE ions concentration.