Total Energy Surfaces: (S₈)_n

Abstract

Although clusters are now routinely observed in mass spectrometers, their most fundamental property, their structure, is still essentially unknown /1/. This is a particularly frustrating state of affairs for the theorists, who, if given the structure, can use their sophisticated methods to calculate the electronic and vibrational properties of clusters. Since experimental investigations have not yet provided much structural information, the theorists have been forced to attack the problem themselves. However, it may be a task which is just beyond the present state of the art. This situation can be contrasted to that which exists in solid state physics where precise structural data is available. One can imagine the confusion which would exist today if the solid state physicist would still have to rely on total energy calculations for the determination of complicated crystal structures. It was the development of diffraction techniques that finally allowed rapid advances in solid state physics. Cluster science awaits a similar breakthrough. In the meantime the cluster theorist faces a challenge even more difficult than that of the solid state physicist. Rather than examining a small set of structures, a vast multidimensional total energy surface must be mapped out and examined /2–4/.