Difference‐frequency laser spectroscopy of the 3ν2+ν3 band of C2H
Difference‐frequency laser spectroscopy of the 3ν2+ν3 band of C2H
复制标题
C2H 3ν2+ν3 波段的差频激光光谱
DOI：
10.1063/1.466084
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发表时间：
1993
影响因子：
4.4
通讯作者：
T. Amano
中科院分区：
文献类型：
--
作者：
Wen;T. Amano
使用高分辨率差频红外激光光谱仪在气相中测量了中心位于 2928 cm−1 的 C2H 2π–2Σ+ 跃迁光谱。 C2H 分子是通过 C2H2 (∼20 mTorr) 和 H2 (∼500 mTorr) 的混合物在空心阴极放电中产生的。采用放电幅度调制技术来提高灵敏度和选择性。对大约 125 条线进行旋转分析，并通过最小二乘拟合确定准确的分子常数。该频带被分配给3ν2+ν3组合频带。该分配与观测到的 2π–2Σ+ 对称性一致，并且与最近的振动频率和自旋轨道耦合常数的理论计算非常一致。 (0 3 1) 态相对较大的自旋轨道耦合常数表明 A 态和 X 态之间存在较强的电子振动相互作用。在观察到的 Q 分支序列末尾附近出现了一个小扰动，这可能是由 Σ 振动态引起的。新辅助...
A spectrum of C2H 2Π–2Σ+ transition centered at 2928 cm−1 has been measured in the gas phase using a high resolution difference‐frequency infrared laser spectrometer. The C2H molecules are produced in a hollow cathode discharge through a mixture of C2H2 (∼20 mTorr) and H2 (∼500 mTorr). The discharge amplitude modulation technique is used to enhance sensitivity and selectivity. About 125 lines are rotationally analyzed and accurate molecular constants are determined through a least‐squares fit. The band is assigned to the 3ν2+ν3 combination band. The assignment is consistent with the observed 2Π–2Σ+ symmetry and is in good agreement with the recent theoretical calculation of the vibrational frequency and the spin–orbit coupling constant. The relatively large spin–orbit coupling constant of the (0 3 1) state is indicative of strong vibronic interaction between the A and X states. A small perturbation appears near the end of observed Q‐branch series, which is probably caused by a Σ vibronic state. New assi...