Isotope Shifts and Rotational Analysis of the As32S+A1Π–X1Σ Band System

Abstract

The emission spectrum of As32S+ and As34S+ has been excited in a quartz discharge tube by a 27 MHz oscillator. Vibrational isotope shifts have verified the vibrational quantum numbers of the upper and lower states. The 2–0, 1–0, 1–1, 0–1, 2–1, and 1–2 bands were chosen for the first rotational analysis of the As32S+ spectrum. The analysis has established that the transition is 1Π–1Σ. The principal molecular constants are as follows:[Formula: see text]Calculated dissociation energies based on the above constants and observed Tc suggest that X1Σ and A1Π have a common dissociation limit, As+(3P) + S(3P). In the upper state several perturbations have been found.