The two GA implementations are conceptually identical except for inclusion of the local optimization procedure directly after the creation of a new offspring particle. We have opted for a pool-based approach where a newly created offspring is immediately added to the population. For offspring creation we implemented two operators, the Cut-and-Splice operator, and an exchange operator, which would randomly exchange atoms of two species. Multiple exchanges are possible with the with the probability of n exchanges being p(n) = 2 -n . Probabilities for the application were 0.4 for the cut-and-splice operator and 0.6