Theoretical study of small silicon clusters: Cyclic ground state structure of Si3

Abstract

The ground state structure of Si3 is found to be cyclic (1 A 1, C2v symmetry) with an apex bond angle of ≂80°. The linear form, analogous to the known structure of C3, is found to be a saddle point which transforms without activation to the cyclic structure. There is a low‐lying triplet state (3 A ’ 2, D 3h symmetry) which lies only a few kcal/mol higher in energy. The nature of the bending potential surface of the ground state structure is also discussed.