Abstract The Fourier transform infrared (FTIR) spectrum of the ν 12 fundamental band of ethylene- 13 C 2 ( 13 C 2 H 4 ) was recorded with an unapodized resolution of 0.004 cm −1 in the frequency range from 1380 to 1500 cm −1 . Rovibrational constants for the upper state (ν 12 =1) up to five quartic and three sextic centrifugal distortion terms were derived for the first time by assigning and fitting a total of 1177 infrared transitions using a Watson's A -reduced Hamiltonian in the I r representation. The rms deviation of the fit was 0.00045 cm −1 . The ground state rovibrational constants were also determined for the first time by a fit of 738 combination differences from the present infrared measurements, with a rms deviation of 0.00060 cm −1 . The A -type ν 12 band with a band center at 1436.65411±0.00005 cm −1 was found to be relatively free from local frequency perturbations. The inertial defect Δ 12 was found to be 0.24300±0.00002 uA 2 .

中文翻译：

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使用高分辨率 FTIR 光谱分析乙烯-13C2 的 ν12 波段

摘要 乙烯- 13 C 2 ( 13 C 2 H 4 ) ν 12 基带的傅里叶变换红外 (FTIR) 光谱在 1380 至 1500 cm -1 的频率范围内以 0.004 cm -1 的非变迹分辨率记录. 通过在 I r 表示中使用 Watson 的 A 约化哈密顿量分配和拟合总共 1177 个红外跃迁，首次推导出了上态 (ν 12 = 1) 最多五个四次和三个六次离心畸变项的旋转振动常数. 拟合的均方根偏差为 0.00045 cm -1 。基态振动常数也首次通过对来自当前红外测量的 738 个组合差异的拟合确定，均方根偏差为 0.00060 cm -1 。A 型 ν 12 带，带中心在 1436.65411±0。发现 00005 cm -1 相对不受局部频率扰动的影响。发现惯性缺陷Δ 12 为0.24300±0.00002 uA 2 。