Second-moment interatomic potential for aluminum derived from total-energy calculations and molecular dynamics application

We have obtained an interatomic potential for Al within the second-moment approximation of the tight-binding theory by fitting to the volume dependence of the total energy of the metal, computed by first-principles APW calculations. This scheme was applied to calculate the bulk modulus, elastic constants, vacancy formation and surface energies of Al. The predicted values are in good agreement with the measurements. We also have used this potential to perform molecular-dynamic simulations and determine the temperature dependence of the lattice constant and atomic mean-square displacements (MSDs), as well as the phonon spectra and surface related thermodynamic properties. A satisfactory accuracy has been obtained, denoting the success of the method.