An improved kinetic Monte-Carlo algorithm for the simulation of atom configuration kinetics in intermetallics was introduced, wherein a set of jump probabilities was computed from energy barriers. In transition state theory the barrier height was the difference between the initial equilibrium state and a saddle-point state. It was on the latter point that traditional treatments had made the most far-reaching assumptions, and had generally set it equal to a constant. A more detailed treatment of the saddle-point state, based upon ab initio calculations of the actual jump profiles, was proposed and demonstrated for Ni3Al. It was shown in preliminary kinetic Monte-Carlo simulations that individually computed saddle point energies made a considerable difference in jump statistics and overall kinetics of the long range order parameter.

Monte-Carlo Simulation of Atom Kinetics in Intermetallics: Correcting the Jump Rates in Ni3Al. Leitner, M., Vogtenhuber, D., Pfeiler, W., Püschl, W.: Intermetallics, 2010, 18[5], 1091-8