THE NEAR-ULTRAVIOLET ABSORPTION SPECTRUM OF CS₂

Abstract

A study has been made of high-resolution absorption spectra of C 12 S 2 and C 13 S 2 in the region 4300–3300 Å. The spectra are shown to arise from transitions from the ground state to two or more excited electronic states. In the lowest excited state the molecule is not linear, and the following constants have been derived for C 12 S 2 32 :[Formula: see text]There is some uncertainty as to the absolute values of v 2 , and this greatly influences the determination of v 3 and v 000 . With the most probable numbering, v 2 = 940 cm −1 and v 000 = 26187 cm −1 . From a study of the four isotopic species C 12 S 2 32 , C 12 S 32 S 34 , C 13 S 2 32 , and C 13 S 32 S 34 , it is found that, in addition to a stretching and bending force constant, two large interaction constants are needed to describe the force system. Data on the higher excited states are fragmentary. The species of the electronic states is still in doubt.