SOME PHYSICAL-PROPERTIES OF NEW OXYFLUORIDE GLASSES

New glasses have been synthesized in the quaternary system based on co mplex molybdenum oxyfluorides. Systematic investigations were implemen ted in the MoO3-BaF2-NaF-ZnF2 quaternary system with a constant amount (30 mol%) of MoO3. Samples of a few mm in thickness were obtained. Th e physical properties such as density, molar volume, glass transition temperature, activation energy of crystallization, stability criterion , thermal expansion coefficient, refractive index, molar refractivity and infrared measurements were performed and correlated with compositi on, especially with alkali fluoride content. By comparison with standa rd fluoride glasses, these glasses exhibit similar characteristic temp eratures but higher refractive index and high ultraviolet absorption.