Laser magnetic resonance spectroscopy of the ν2 fundamental band of DO2 at 9.8 μm

Abstract

The ν2 fundamental band (bending vibration, ν0=1020.162 cm−1) of the deuteroperoxyl radical DO2 has been studied using the technique of laser magnetic resonance, in which molecular transitions are tuned into resonance with fixed laser lines by means of the Zeeman effect. The DO2 was produced in a flow system by reacting the products of a discharge in O2 with methanol (CH3OD or CD3OD) or ethanol (C2H5OD). About 150 resonances, observed using 19 different CO2 laser lines in the 1009–1038 cm−1 region, were assigned to DO2 transitions with 1⩽N⩽9 and 1⩽Ka⩽6. Their analysis yielded the ν2 band origin as well as rotation, spin–rotation, and centrifugal distortion parameters for the ground and ν2 excited vibrational states. It was necessary to include in the analysis the effects of Coriolis interaction between ν2 and ν3, which lies about 100 cm−1 higher in energy. Thus the Coriolis coupling constant and some effective ν3 band parameters were also determined, though ν3 was not observed directly.