Structural stabilities of small sulfur clusters

We acquired 68 small sulfar clusters from S-3 to S-13 with molecular graphi cs and then carried out the optimizations and vibrational frequencies by de nsity functional calculations. The non-minimum structures with negative vib rational frequencies were excluded. When designing these isomers, the sulfu r atoms could be in one-fold, two-fold and three-fold. The sulfur clusters with three-fold atom are higher in energies. It is rare to form a cage stru cture with multi-fold atom(s). By comparing the total energies of the diffe rent isomers, the energies of ring structures are higher than those of chai n ones from S-5. The large neutral sulfur clusters are mostly ring structur es.