Infrared absorption spectroscopy of CO2–HX complexes using the CO2 asymmetric stretch chromophore: CO2HF(DF) and CO2HCl(DCl) linear and CO2HBr bent equilibrium geometries
Infrared absorption spectroscopy of CO2–HX complexes using the CO2 asymmetric stretch chromophore: CO2HF(DF) and CO2HCl(DCl) linear and CO2HBr bent equilibrium geometries
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使用 CO2 不对称拉伸发色团的 CO2-HX 复合物的红外吸收光谱：CO2HF(DF) 和 CO2HCl(DCl) 线性和 CO2HBr 弯曲平衡几何形状
DOI：
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发表时间：
1990
期刊：
影响因子：
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通讯作者：
R. Beaudet
中科院分区：
文献类型：
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作者：
S. Sharpe;Y. Zeng;C. Wittig;R. Beaudet
使用可调谐二极管激光光谱和脉冲狭缝扩展（0.15×38 mm 2），记录了CO2与HF、DF、HCl、DCl和HBr的弱键合气相复合物与CO2不对称伸缩振动相关的红外吸收光谱，提供>20 MHz的总分辨率。用CO2-HF获得的结果与早期的研究一致，其中检查了3900 cm−1附近的HF拉伸区域。在这两种情况下，宽线宽表明亚纳秒预解离。使用CO2-DF，自然线宽明显窄于CO2-HF（例如，28与182 MHz），这种差异是由于较慢的预解离，可能涉及共振的情况下的CO2-HF。CO2-HF和CO2-DF表现出重叠的功能：简单的P和R分支与线性转子，P和R分支含有双峰。在早期的研究中，第二个特征可以被分配给Ka=1的略微不对称转子，或者涉及低频中频的热区。
Infrared absorption spectra associated with the CO2 asymmetric stretch vibration have been recorded for weakly bonded gas‐phase complexes of CO2 with HF, DF, HCl, DCl, and HBr, using tunable diode laser spectroscopy and a pulsed slit expansion (0.15×38 mm2) that provides >20 MHz overall resolution. Results obtained with CO2–HF are in agreement with earlier studies, in which the HF‐stretch region near 3900 cm−1 was examined. In both cases, broad linewidths suggest subnanosecond predissociation. With CO2–DF, the natural linewidths are markedly narrower than with CO2–HF (e.g., 28 vs 182 MHz), and this difference is attributed to slower predissociation, possibly implicating resonances in the case of CO2–HF. Both CO2–HF and CO2–DF exhibited overlapping features: simple P and R branches associated with a linear rotor, and P and R branches containing doublets. As in earlier studies, the second feature can be assigned to either a slightly asymmetric rotor with Ka=1, or a hot band involving a low‐frequency intermo...