High-Magnetic-Moment Icosahedral Clusters

The icosahedral group is the largest nonaxial group. An object with icosahedral 

The most stable clusters should have all degenerate levels either empty or completely filled. Next in order of stability should be clusters that have degenerate 

One can consider bonding to the icosahedral shell of atoms as a whole [54,55]. The optimized electronic structure of icosahedral Fe12 is open-shell, 

The non half-filled open subshell is the l hg, a d-like molecular orbital. It has 3 electrons. Adding two electrons will make it half filled. Subtracting three will make it empty. This suggests looking at di- and tri-valent atoms to put in the center position to stabilize this icosahedral shell. (Other valences could also work by filling or half-filling other orbitals. Table 1 give the Jahn-Teller stable clusters found in a study of 13 different candidates for the central atom [55]. 

Central atom Binding energy Radial bond distance Unpaired electrons 

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