Brillouin scattering study of elastic properties in a glass forming KNO3–Ca(NO3)2 mixture

Brillouin scattering (GHz) experiments were performed on a glass-forming 60% KNO3–40% Ca(NO3)2 mixture (mol %) through the glass transition in a temperature range of 295–398 K. Sound velocities for the transverse and longitudinal waves were determined both in the glass and in the melt. The elastic constants and the modulii in the glass and the shear modulus of the melt were evaluated as a function of temperature. The hypersonic results of the glass agree, within the experimental error, with ultrasonic results obtained at room temperature. Present hypersonic values for the shear modulus of the melt, calculated from the transverse velocity at infinite frequencies, are considerably larger than those reported from ultrasonic studies.