Structural evolution and magnetic properties of ScLi_n (n=2-13) clusters: A PSO and DFT investigation

The stable geometries, electronic structures, and magnetic behaviors of the ScLi_n (n=2-13) clusters are investigated by using particle swarm optimization (PSO) and density functional theory (DFT). The results show that these clusters have three-dimensional (3D) structures except ScLi₂, and ScLi₁₂, and ScLi₁₃ that possess the cage-like structures. In analyses of the average binding energy, second-order difference of energy, and fragmentation energy, ScLi₁₂ cluster is identified as magnetic superatom. The magnetic moment for each of these clusters owns an oscillating curve of different cluster sizes, and their magnetic moments are further investigated using molecular orbitals and jellium model. Of ScLi_n (n=2-13) clusters, ScLi₁₂ has the largest spin magnetic moment (3 μ_B), and molecular orbitals of ScLi₁₂ can be described as 1S²1P⁶1D_α⁵D_β². Additionally, Mulliken population and AdNDP bonding analysis are discussed and the results reveal that the Sc atom and Li_n atoms make equal contribution to the total magnetic moment, and atomic charges transfer between Sc atoms and Li atoms.