Sound Wave Propagation in Immiscible AgBr+LiCl Melts

Abstract

Abstract The velocity of sound wave propagation was measured for the biphasic region of AgBr+LiCl melts using the pulse method at temperatures from melting point to mixing temperature. It was found that temperature dependences of sound velocities on the saturation lines have opposite signs because of the different effect of thermal motion of the particles and the phases’ composition at the sound velocity. The difference between the sound velocities in the coexisting phases, Δu, is described by the exponential equation Δu≈(Tc−T)θ where the exponent is 0.865. This index is close to the values found in salt families formed with silver iodide and lithium and sodium halides but occurs at a lower value than that found for alkali halide melts between each other. The sound velocities in the phases take the same value 1612 m s−1 at the upper critical consolute temperature Tc=843 K. For a family of stratified silver halide containing melts, the versatility of the temperature dependence of the sound velocity near the critical point of mixing is declared. The sound velocity is discussed from the viewpoint of the different character of chemical bonds of salts.