A modification of the Finnis-Sinclair potentials for highly deformed and defective transition metals

A modification is introduced to the original Finnis-Sinclair potentials for transition metals which substantially improves their pressure versus volume behaviour and overcomes their high-compression instability. With this modification good results are obtained for the energetics instability. With this modification good results are obtained for the energetics and the stable configuration of vacancies and interstitials. Excellent agreement is also found between the lattice parameter dependence of the cohesive energy of Mo as obtained using the modified potentials and via self-consistent augmented-spherical-wave calculations. With the proposed modification, the repulsive component of the modified potentials turns out to be akin to a Wedepohl potential.