Second moment approximation of tight-binding potential for γFe applicable up to 1700 K

The atomic potential of γFe has been constructed on the basis of the second-moment approximation of the tight-binding scheme potential. To apply this potential to molecular dynamics simulations at high temperatures up to about 1700 K, the cut-off distance has been set to the sixth neighbours and other parameters have been determined from fitting to physical properties of γFe such as the cohesive energy, vacancy formation energy, lattice constant, elastic constants and bulk modulus. This potential can also describe the temperature dependencies of the lattice constant and the specific heat at constant pressure and can simulate hypothetical melting of γFe.