Uv Absorption Spectrum of Trapped S2

Abstract

The uv absorption spectrum of trapped S2 has been studied in N2, Ar, Kr, and Xe matrices at 4° and 20°K. Up to 26 vibrational bands of the v″=0 progression of the 3Σu—←3Σg— system were observed. In each of the matrices, the origin of the transition was shifted by an amount characteristic of the particular matrix; red shifts were observed for Xe, Kr, and Ar, while N2 yielded a blue shift. The vibrational spacing indicated distortion of the potential-energy curve under the influence of the matrix field. The absorption bands were slightly shaded towards the blue and had a half-width of about 150 cm−1. At low v′, doublet structure was observed. The ir absorption spectrum of the forbidden S2 vibration was also investigated.