Genetic algorithms 4 Atomic cluster structure 2 Atomic cluster structures 2 Crystal atomic structure 2 Global optimization 2 Medium-sized silicon clusters 2 Probability density function 2 Semiconducting silicon 2 Silicon clusters 2 Structural motifs 2 article 2 atomic particle 2 cluster analysis 2 copper 2 density functional theory 2 energy 2 genetic algorithm 2 silicon 2 structure analysis 2