Abstract The vacuum-ultraviolet photoionization efficiency spectroscopy (PIES) of carbon monoxide in a region 575–890 A has been investigated with time-of-flight (TOF) photoionization mass spectrometry (PIMS) by using tunable synchrotron radiation (SR). Three photoionization thresholds were determined to be 14.015, 16.550 eV and 19.670 eV for the X2Σ+, A2Π and B2Σ+ states of CO+, respectively, which are in very good agreement with those of previous investigation. Furthermore, the Rydberg series converging to the X2Σ+, A2Π, B2Σ+, D 2Π and C 2Σ+ states of CO+ were assigned clearly, according to the PIES of CO and calculation with Rydberg series formula. In particular, the Rydberg series (Rx-I) (v+ = 2, 3 and 4) and Rx-TTI series (ν+ = 1,2,3 and 4) converging to CO+ (X2Σ+), the Rydberg series (RB-V) (v+ = 1, 2 and 3) converging to CO+ (B2Σ+), and a new vibrational progression (n = 2) converging to CO+ (A2Π) were all identified and listed for the first time. Generally speaking, the Rydberg series identified in this work are in good accordance with those of previous study. Moreover, some of them are extended to higher number, and some new members are classified for the first time.

中文翻译：

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利用同步辐射研究从电离阈值到 575 Å 一氧化碳的光电离质谱

摘要 使用可调谐同步辐射 (SR) 的飞行时间 (TOF) 光电离质谱 (PIMS) 研究了 575–890 A 区域内一氧化碳的真空-紫外光电离效率光谱 (PIES)。CO+ 的 X2Σ+、A2Π 和 B2Σ+ 状态的三个光电离阈值分别确定为 14.015、16.550 eV 和 19.670 eV，这与之前的研究非常吻合。此外，根据CO的PIES和Rydberg级数公式计算，明确指定了收敛于CO+的X2Σ+、A2Π、B2Σ+、D 2Π和C 2Σ+态的里德堡级数。特别地，里德堡级数 (Rx-I) (v+ = 2, 3 和 4) 和 Rx-TTI 级数 (ν+ = 1,2,3 和 4) 收敛于 CO+ (X2Σ+)，里德堡级数 (RB -V) (v+ = 1、2 和 3) 收敛于 CO+ (B2Σ+)，和一个新的振动级数 (n = 2) 收敛到 CO+ (A2Π) 都被首次识别和列出。总的来说，本工作确定的里德堡级数与前人的研究结果吻合较好。而且，其中一些扩展到更高的数量，并且一些新成员是第一次分类。