MRD CI calculations of excited states of the SiH 3 radical, including potential curves for the inversion mode and the dissociation SiH 3 → SiH 2 + H

Abstract

Using the MRD CI method and large basis sets the vertical spectrum of silyl radical (SiH 3) has been calculated. The lowest excited state is the 4s Rydberg state, 41000 cm −1 (5.2 eV) above the ground state. Only one excited valence state (2 2E) was encountered, all other states are of Rydberg type. From potential curves for the inversion mode (symmetric bending motion) it was inferred that all Rydberg states are planar, whereas the valence excited state is highly pyramidalized. The investigation of the dissociation reaction SiH 3 → SiH 2 + H leads to the conclusion that the first excited state is dissociative.