Synthesis, structure and nonlinear optical properties of tellurium oxide - bismuth oxide - boron oxide glasses

TeO2-Bi2O3-B2O3 glasses are prepared using a conventional melt-quenching method. The polarizability approach based on the Lorentz-Lorenz equation is applied and the optical basicity and the oxide ion polarizability are estimated. The glasses possess relatively high values of the optical basicity (0.734-0.936) and the electronic oxide ion polarizability (1.785-2.276 angstrom(3)). The theoretical refractive index of the glasses is also estimated. On this basis the third order nonlinear optical susceptibility of the glasses is established using generalized Miller's rule. The glasses possess comparatively high third order nonlinear optical susceptibility in the 0.64-2.31x10(-13) esu range. The chemical bonding of the glasses is elucidated on the basis of the interaction parameter and the single bond strength of an average cation-oxide ion (M-O) bond. It is found that the glasses possess relatively low values for the average single bond strength (352-254 kJ/mol) and low values of the interaction parameter (0.051-0.028 angstrom(3)). These results indicate for the presence of weak chemical bonds which are formed between TeO4, TeO3, BiO6, BO4 and BO3 groups confirmed by IR spectral analysis.