Thermoacoustic parameters of rare earth and reference materials at 298 K

Abstract

Thermoacoustic properties of various rare earth and reference materials have been evaluated from volume expansivity ( α) data at 298 K. Moelwyn–Hughes parameter ( C 1) has been utilized as a fundamental parameter because of its importance in connection with the lattice Grüneisen parameters ( Γ), the free available volume ( V a/ V), the repulsive exponent of intermolecular potential ( n), the reduced molar volume ( Ṽ), the reduced bulk modulus ( B̃), isochoric acoustical parameter ( Δ), the Anderson–Grüneisen parameter ( δ), and molecular constant. The average value of ( V a/ V) for these materials is about 0.007. It is quite evident from this study that Γ iba > Γ ith for reference and rare earth materials. Sharma's acoustical parameter ( S 0), which is a characteristic of wide variety of substances has been found to be approximately a constant value of 1.104 ± 0.003 in the case of rare earth and reference materials studied.