Refractive indices and molar refraction of molten binary of lithium, sodium and potassium tungstate and bitungstate mixtures

Refractive indices of molten binary mixtures of lithium, sodium and potassium tungstates and ditungstates. Are measured by ellipsometric method depending on the temperature and chemical compposition. Their molar refraction changing weakly with the temperature is calculated. Polarization and radius of WO42- anion and WO3 molecule in molten lithium, sodium, potassium tungstates and quasiliquid tungsten trioxide are evaluated