EFFECTS OF CLUSTER-CLUSTER INTERACTIONS ON THE STRUCTURE AND MAGNETIC-PROPERTIES IN (FE-6)(2)

The structure and magnetic properties of the coupled Fe-6:Fe-6 cluster have been systematically studied with the density functional formalis m, and the Kohn-Sham equation is solved self-consistently with the dis crete variational method (DVM). It is found that as the intercluster d istance decreases the clusters are deformed, which results in the sens itive changes of magnetic moments. The cluster-cluster coupling energy indicates that the two clusters are weakly coupled, and the HOMO-LUMO gap of the coupled clusters is so small that the two coupled Fe-6 clu sters are nearly metallic, and the metal-nonmetal transition can be re alized by coupling and decoupling of clusters. (C) 1998 Elsevier Scien ce S.A.