S2 (a 1Δ) production in the photolysis of reduced sulfides: production chemistry, spectroscopy and interference potential in the LIF detection of OH

Production of S2 (a 1Δ, v=2) has been observed in the UV photolysis of several reduced sulfur compounds by monitoring the f 1Δ–a 1Δ (2–3) laser excitation spectrum. There appears to be at least three production mechanisms including reaction of S (1D) with the precursor. The f–a (2–3) band shows several spectral overlaps with the OH A 2Σ–X 2Π (1–0) band including the Q11 line. Since a significant fraction of the f–a emission from f 1Δ (v=2) overlaps the OH A–X (1–1) and (0–0) bands the potential for a significant `interferenceʹ signal exists if the two species are produced simultaneously.