Atomic migration and ordering energies in FePd: Measurement and modeling

Atomic migration energies of 0.91 eV, 0.66 eV and 0.74 eV have been deduced in FePd from the phonon density of state in the L10 phase at 300 K and 860 K, and in the face-centered cubic phase at 1020 K, respectively. A good agreement is observed with the resistivity measurement results. Effective pair interactions have been determined using both an inverse cluster variation and an inverse Monte Carlo method. The results of the two methods agree well and lead to the predominance of the second effective pair interaction V2. The relevance of the deduced pair interactions is tested in terms of order-order and order-disorder kinetics simulations using a Monte Carlo model.