Two-color resonance two-photon ionization and mass analyzed threshold ionization spectra of 2-aminobenzonitrile have been obtained. The band origin of the S₁←S₀ transition and the precise ionization energy (IE) were determined to be 31265 ± 2 cm^-1 and 66653 ± 5 cm^-1, respectively. The most active modes in the S₁ and D₀ states are related to the in-plane ring vibrations. The relative errors of IE estimated by CBS-QB3 and G4 are -0.18% and +1.47%, respectively. The theoretical calculations well support our experimental findings.

中文翻译：

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2-氨基苄腈的双色共振增强多光子电离和质谱分析阈值电离光谱及其CN取代效应

获得了2-氨基苄腈的双色共振双光子电离和质量分析阈值电离光谱。S ₁ ← S ₀跃迁的能带起点和精确电离能（IE）分别确定为31265±2 cm ^-1和66653±5 cm ^-1。在S ₁和D ₀状态下最活跃的模式与面内环振动有关。CBS-QB3和G4估计的IE的相对误差分别为-0.18％和+ 1.47％。理论计算很好地支持了我们的实验结果。