Elastic Behaviour and Lattice Vibrations in bcc V and Nb

A model is developed by extending the generalised form of exponential potential known as extended generalised exponential potential to account for: (a) a realistic realization of interactions in all separations in general and that of small separations in particular, (b) three-body and electronic effects into the interaction in an alternative and simpler form, (c) a model free from usual fitting procedure. The model is employed to compute the cohesive energy, phonon spectra and second- and third-order elastic constants for group VA bcc metals V and Nb. The computed results showing good agreement with the experimental findings lend reliability and credibility to the potential.