The cage‐like structure enhanced magnetic moment in ScKn (n = 2–12) clusters: A first‐principles jointed particle swarm optimization investigation

Abstract

AbstractUsing the first principles method combined with the CALYPSO structure prediction method, the authors have investigated the geometries of the lowest‐energy and its isomers of ScKn (n = 2–12) clusters, and the electronic configurations and magnetic moments of each clusters. With the increasing size of ScKn clusters, the transition‐metal Sc atom gradually slides from the corner (for n ≤ 8) to core of cage‐like structures (for n > 9). After detailed check out the binding energy per atom Eb, second‐order difference of energy ∆E, and fragmentation energies Ef, the authors found out that the cage‐like ScKn (n = 9–12) clusters are more stable than the small‐sized ScKn (n = 2–8) clusters, and the ScK8, ScK10, and ScK12 are more stable than their neighbors. The enhanced magnetic moments are found in ScKn (n = 9–12) clusters whose total magnetic moments are 2, 3, 4, and 5 μB, respectively. The origination of the enhanced magnetic moments is further investigated using the Mulliken population, the molecular orbitals and the chemical bonding analysis. The results show that the large magnetic moments have relation with the interaction between Sc and K atoms. The valence shell of superatom ScK12 cluster can be described as 1S21P61D52S2, which made its magnetic moments as large as 5 μB.