Study of geometries of the Cu₁₃ cluster using the genetic algorithm and density-functional calculations

Geometrical structures of Cu₁₃ cluster are calculated by a genetic algorithm combined with the Gupta inter-atomic potential systematically, and the obtained structures are re-optimized in further by density-functional theory (DFT) calculations. Our results show that: though the high-symmetric compact ground-state structure obtained by Gupta potential is not the same one as that obtained by DFT which favors a non-compact low symmetric ground-state, from re-optimization by DFT of the large number of initial structures provided by Gupta potential, one still can find the true ground-state geometrical structure, which means that the genetic algorithm can still offer the efficiency of structure optimization in dealing with a system with non-compact low symmetric ground-state geometry. (authors)