The local magnetic properties of sp impurities in alkali metal clusters

Abstract

The local magnetic properties of sp impurities (B, C, N, O) in alkali metal clusters (Li 12, Na 12, K 12, Rb 12) with I h and O h symmetries have been systematically studied within the density functional formalism, and the Kohn-Sham equation is solved self-consistently using the discrete variational method (DVM). It is found that all the impurities in clusters are magnetic, especially the local moment of impurity O in bulk is small, but a large moment appears in clusters. Of all the clusters, impurity N in Rb 12 has the largest moment of 2.50 μ B. For impurity C in K 12 and Rb 12, the moments are close to the values of interstitial impurity in bulk, for impurity N in Na 12, K 12 and Rb 12, the moments are close to the values of substitutional impurity in bulk. The stability of clusters is also studied: the I h structure is more stable than O h, Li 12O, Na 12O, K 12O and Rb 12O have closed shells, the gap between the highest occupied molecular orbital (HOMO) and the lowest unoccupied molecular orbital (LUMO) indicates that the greater the gap, the greater the binding energy.