Mathematical model for ion refractivity of oxygen in slags

A mathematical model to estimate the ion refractivity of oxygen in the binary and ternary silicate systems has been developed based upon a simple structural model for silicate glasses. The ion refractivity R-o of oxygen in binary silicate glasses can be described by the equation R-o = R-o(o) + Delta R-o[2x/(2-x)], where R-o(o) and Delta R-o are the ion refractivity of oxygen for SiO2 glass and the increase in the ion refractivity of oxygen due to the presence of non-bridging oxygen ions, respectively, and x is the mole fraction of alkali or alkaline earth metal oxide. Published data for the ion refractivity of oxygen for alkali and alkaline earth silicate glasses have supported that this model is reasonable, and values of Delta R-o, have been determined as 0.69 for Li2O, 1.19 for Na2O, 1.56 for K2O, 1.10 for CaO and SrO, and 1.30 for BaO. The value of QR, means the effective basicity for these oxides doped into SiO2 glass. Furthermore, the model has been extended to the ternary silicate system.