Recent work has shown that the vibrational properties of solids may be calculated to some approximation by using small clusters such that the surface atoms have an additional potential upon them. This potential, which is complex and frequency dependent, is determined by demanding that the average mean square displacements of the surface and bulk atoms is the same.In this paper, the work is extended from the basic tetrahedral unit of Si/Ge to larger structural units ‐ pentagonal and hexagonal rings. These yield characteristic densities of states which are not very different from those obtained previously for the tetrahedral unit. The implications of this result are discussed.