Effect of alkali metal oxides R2O (R = Li, Na, K, Rb and Cs) and network intermediate MO (M = Zn, Mg, Ba and Pb) in tellurite glasses

A systematic characterization of optical, chemical and thermo-mechanical properties of R2O-MO-TeO2 glasses as function of alkali metals as network modifiers and network intermediate was performed. Properties such as thermal expansion coefficient (alpha), glass transition temperature (T-g), refractive index (n), transmittance, chemical durability (DR), density (rho) and the third-order nonlinear optical susceptibility (chi((3))) were measured and it was found that both components R2O and MO, have great influence on such properties. Experimental results indicate that alkali metals with small ionic radii improve chemical durability (DR) and mechanical (alpha, T-g) properties. They also increase n and chi((3)). Lower thermal expansion coefficient was obtained for Zn and Mg while better chemical durability corresponds to Pb and Zn. (C) 2008 Elsevier B.V. All rights reserved.