Copper-carbon clusters CunCm (n, m = 1–6): Segregation, bonding and Raman spectra

Structural and electronic properties of the lowest-energy structures of CunCm (n, m = 1–6) clusters have been calculated using density functional theory. Among these thirty-six doped clusters, the segregation effect between carbon and copper atom is observed and C-clumping maintains the chain structure. The relative stabilities of CunCm have been examined by means of the averaged atomic binding energies, the second-order difference of energies and the fragmentation energies. The calculated electron localization function and Mayer bond order are in good agreement with adaptive natural density partitioning. The analysis of the structure and bonding properties of the weak Cu-C interaction contributes to understanding the growth mechanism of catalytic carbon fibers.