Insights into geometries, stabilities, electronic structures, reactivity descriptors, and magnetic properties of bimetallic Ni m Cu n-m (m = 1, 2; n = 3-13) clusters: Comparison with pure copper clusters.

A long-range corrected density functional theory (LC-DFT) was applied to study the geometric structures, relative stabilities, electronic structures, reactivity descriptors and magnetic properties of the bimetallic NiCun -1 and Ni2 Cun -2 (n = 3-13) clusters, obtained by doping one or two Ni atoms to the lowest energy structures of Cun , followed by geometry optimizations. The optimized geometries revealed that the lowest energy structures of the NiCun -1 and Ni2 Cun -2 clusters favor the Ni atom(s) situated at the most highly coordinated position of the host copper clusters. The averaged binding energy, the fragmentation energies and the second-order energy differences signified that the Ni doped clusters can continue to gain an energy during the growth process. The electronic structures revealed that the highest occupied molecular orbital and the lowest unoccupied molecular orbital energies of the LC-DFT are reliable and can be used to predict the vertical ionization potential and the vertical electron affinity of the systems. The reactivity descriptors such as the chemical potential, chemical hardness and electrophilic power, and the reactivity principle such as the minimum polarizability principle are operative for characterizing and rationalizing the electronic structures of these clusters. Moreover, doping of Ni atoms into the copper clusters carry most of the total spin magnetic moment. © 2018 Wiley Periodicals, Inc.