Equation of state for transition metals
T. Qin, R. Drautz, D. G. Pettifor.
Physical Review B, 77, 220103,1-4, (2008)
A mixed power-exponential-type potential is proposed for transition metals that overcomes two of the key problems associated with the extended Rydberg potential formalism of the Rose binding-energy relation and the Vinet equation of state. First, it includes naturally the hard-core repulsion at high pressures, and secondly it avoids the convergency problems associated with the series expansion of the Rydberg potential about equilibrium. This potential has been tested against an extensive first-principles database across the transition-metal series. It should prove invaluable to experimentalists in the fitting of their high-pressure data and to theorists in the development of robust interatomic potentials for atomistic simulations.
Keyword(s): total-energy calculations; high-pressure equations; augmented-wave method; universal equation; ground-state; basis-set; features; solids; bands