Laser-Induced Fluorescence and Fourier Transform Spectroscopy of the [21.9]2Δ5/2–X2Π3/2 (21 910 cm−1) and the [21.9]2Δ5/2–[.16]2Δ5/2 (21 750 cm−1) Transitions of NiCl

Abstract

The visible spectrum of NiCl consists of a large number of bands. Laser-induced fluorescence experiments have shown that two intense transitions (21 910 and 21 750 cm−1) share a common [21.9]2Δ5/2 upper electronic state. High-resolution Fourier transform spectroscopy has allowed the rotational analysis of the (0–0), (1–0), and (0–1) bands of the [21.9]2Δ5/2–[0.16]2Δ5/2 transition and the (0–0) band of the [21.9]2Δ5/2–X2Π3/2 transition. No fluorescence to a state lower in energy than the X2Π3/2 state was observed in our experiments. We believe that we have identified the 2Π3/2 spin–orbit component of the X2Πi ground state and the 2Δ5/2 spin–orbit component of the first A2Δi electronic state.