The structure of small metal clusters

Abstract

One metal atom surrounded by its 12 nearest neighbors is considered for both D 3d (face‐centered cubic‐like) and D 3h (hexagonal close‐packed‐like) geometries. For Al and Be, the neutral cluster and the positive and negative ions are considered for idealized (all bonds equal) and distorted geometries. The D 3d geometry is found to be the lowest for Be1 3, while the D 3h geometry is lower for Al1 3. This is the reverse of what is expected based upon the bulk metal structures, Be(hcp) and Al(fcc). Al1 3 is found to have only small distortions, while Be1 3 shows large distortions for both the D 3d and D 3h geometries. The ions have geometries which are similar to those found for the neutral systems. Both all‐electron and effective core potential calculations were carried out on the X1 3clusters; the agreement is very good.