The Influence of MnO on Polaron Radius and Field Strength of Sodium Zinc Phosphate Glass Matrix
Y.H. Elbashar and D.A. Rayan
The present work describes preparation of a glass matrix with chemical formula 40P2O5-39ZnO-(21-x)Na2O-xMnO (where, x varied from 1 to 6 mol%) by traditional melt quenching technique and study of its some physical properties such as polaron radius and field strength. The glass samples densities were increased and those of the molar volume were decreased by increasing the content of MnO. In addition, the concentration of manganese ions and the related field strength were increased while the corresponding inter-ionic spacing and polaron radius were decreased. The spectroscopic studies of all samples were carried out over (190-2500 nm) spectral range. The optical transmission of the prepared glass in the visible-near IR spectral range is enhanced by increasing the MnO content where it reaches a maximum value of about 86% at concentration 3% of MnO. This excellent transmission in such spectral range suggested the use of the present glass in many technological applications such as modulators and lens applications in the visible band. The optical band gap and the Urbach energies were determined. The refractive index was found to be decreased by increasing the MnO concentration from 1% to 3% then increased by increasing the MnO concentration from 3% to 6%. Other related physical parameters such as dielectric constant, electric susceptibility, molar polarizibility and metallization criterion were evaluated. The results predicted the working of the present glass in the range of nonlinear optical materials.
Keywords: Phosphate Glass, Manganese Ions, Refractive Index, Metallization Criterion, Urbach energy, bandgap