Study of elastic properties of sodium, potassium and rubidium acid phthalates by brillouin scattering

Abstract Elastic properties of three, isomorphous, orthorhombic ( mm 2) molecular-ionic crystals of sodium, potassium and rubidium acid phthalates have been studied employing the Brillouin scattering technique. The values of all elastic constants: stiffnesses c αβ and compliances s αβ were determined at 294 K using the measured longitudinal and transverse sound velocities for different phonon directions.