Ultrasonic Attenuation in Thorium Monopnictides

The ultrasonic attenuation due to phonon-phonon interaction have been computed along <100>, <110> and <111> directions at room temperature. For the evaluation of attenuation, we have also evaluated higher order elastic constant, ultrasonic velocity and acoustic coupling constant. The Coulomb and Born-Mayer potential has been applied to find out the higher order elastic constants in the temperature range 0-300K. Some mechanical constant were also computed for predicting for futuristic performance of the chosen materials. The behaviour of ultrasonic attenuation has been considered in correlated with other thermo-physical properties of thorium monopnictides.