Structural, electronic, magnetic and spectral properties of Cond (n=3–18; d=0, ±1) clusters and the adsorption to CO

Density functional theory and CALYPSO method have been applied to investigate the structural, electronic, magnetic and spectral properties of Co[Formula: see text] ([Formula: see text]–18; [Formula: see text], [Formula: see text]1) clusters and the adsorption of CO molecule. Structural search shows that the growth of the lowest energy cobalt clusters, especially large cobalt clusters, follows certain rules. When [Formula: see text], cobalt atoms grow around an icosahedron. From the ground states we obtained, some electronic and magnetic parameters have been calculated and the calculated results are compared with their experimental results. The stability of the cobalt cluster is analyzed based on the second-order energy difference and energy gap. For the neutral and anionic cobalt clusters, we have simulated their infrared, UV and photoelectron spectra (PES). Meanwhile, their ground-state structures have been confirmed by comparing the theoretical spectra with the experimental spectra. On the other hand, it is found that cobalt clusters have a strong adsorption to CO molecule. The adsorption energy is inversely proportional to the C–Co bond length. The changes in the vibrational frequency of CO molecules adsorbed on cobalt clusters are correlated with the C–O bond length.