1Department of Physics, S.S.V. (P. G.) College, Hapur (UP), India
2Department of Chemistry, S.S.V. (P. G.) College, Hapur (UP), India
3Department of Chemistry, IMS Engineering College, Ghaziabad, (UP), India
4Department of Physics, Government Degree College, Nanouta, Dist.-Saharanpur (UP), India
*E-mail: rishisingh80@rediffmail.com
Online published on 5 August, 2015.
Temperature dependence of acoustical attenuation of fifth group mononitrides (viz. XN, X=V, Nb and Ta) in wide temperature range (50 K-500 K) for longitudinal and shear modes of propagation along <100>, <110> and <111> directions have been calculated. Second and third order elastic moduli have been evaluated using electrostatic and Born repulsive potential taking interaction upto next nearest neighbours. Grüneisen parameters, nonlinearity constants have been evaluated for longitudinal and shear waves along different directions of propagation and polarization. Results have been discussed and it has been found that attenuation contribution due to thermoelastic mechanism is negligible compared to phonon-phonon interaction mechanism.
Acoustic attenuation, phonon-phonon interaction, elastic constants, thermal elastic loss
