Abstract Hyperfine-resolved high-resolution fluorescence excitation spectrum of the A ˜ 2B2 ← X ˜ 2A1 transition of 14NO2 radical in the 15870–15900 cm−1 energy region was observed, by crossing a jet-cooled molecular beam and an output of a single-mode dye laser at the right angles. We obtained the rotational assignments up to N′ = 11 for the Ka = 0 series and those up to N′ = 7 for the Ka = 1 series by analyzing the observed hyperfine structures and employing the combination differences, and determined the molecular constants of the upper vibronic level. Most of the Fermi contact interaction constants of the rotational levels of the upper vibronic level were found to range from 0.002 cm−1 to 0.004 cm−1. The (Ka′ = 0, N′ = 3, J′ = 3.5) level was found to be strongly perturbed, and we recognized some perturbers in the vicinity of the main rotational level. We concluded that the most plausible candidate of the perturbers in this region is the vibronic levels having almost pure A ˜ 2B2 electronic state character.

中文翻译：

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15885 cm−1 能量区中 14NO2 自由基的超精细高分辨率激光光谱

摘要 14NO2 自由基在 15870–15900 cm-1 能量区的 A ～ 2B2 ← X ～ 2A1 跃迁的超精细高分辨率荧光激发光谱被观察到，通过穿过喷射冷却的分子束和单个输出-模式染料激光在直角。通过分析观察到的超精细结构并利用组合差异，我们获得了 Ka = 0 系列的高达 N' = 11 的旋转分配和 Ka = 1 系列的高达 N' = 7 的旋转分配，并确定了分子常数。上振动水平。发现上振动能级的旋转能级的大多数费米接触相互作用常数范围从 0.002 cm-1 到 0.004 cm-1。发现 (Ka' = 0, N' = 3, J' = 3.5) 能级受到强烈干扰，我们在主旋转平面附近发现了一些干扰物。我们得出结论，该区域中最可能的扰动候选者是具有几乎纯 A ～ 2B2 电子态特征的振动能级。