Role Of The Zinc Cation In The Structural Ordering In Sodium Zinc Silicates

The evolution of the "boson peak" contour in low frequency Raman spectra of a few Na20-Zn0-Si02 compositions was observed under subsequent substitution of Na20 for ZnO. Frequency shift of this mid-order sensitive feature shows a decrease of the glass correlation radius with an increase in zinc oxide concentration (while keeping the SiO2 content constant). In structural terms, the correlation sphere size reflects the dimension of the glass cell unit. In terms of physical properties, the effect is connected with the densification of the glass resulting from a change of modifying ions.