The laser magnetic resonance spectrum of the NCO radical at 5.2 μm

Abstract

Lines in the ν 3 (“antisymmetric” stretch) fundamental of the NCO radical in the X ̃ 2 Π state were studied by CO laser magnetic resonance. The observations were assigned to P and R lines in the vibration-rotation band and lead to a precise determination of the vibrational interval and the anharmonic correction to the rotational constant: ν 3 = 1920.60645(19) cm −1, α 3 = 0.003338(21) cm −1. A single transition in the hot band (011)-(010), 2 Δ 5 2 - 2 Δ 5 2 was detected. This observation is used to determine the origin of the hot band as 1907.11892(20) cm −1, i.e., the anharmonicity parameter x 23 = −13.48753(28) cm −1.