Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge, CB2 1EW, UK.
Phys Chem Chem Phys. 2011 Sep 7;13(33):15318-25. doi: 10.1039/c1cp21337g. Epub 2011 Jul 26.
A dual wavelength range spectrometer system has been designed and constructed which can simultaneously perform single pass UV absorption spectroscopy and cavity enhanced absorption spectroscopy in the green region of the visible spectrum. Using the system the absorption spectrum of molecular chlorine has been measured, in the wavelength range 509-570 nm, using cavity enhanced absorption spectroscopy. Absolute absorption cross sections were obtained by simultaneous measurement of the UV spectrum to obtain the Cl(2) concentration. These are the first temperature dependent measurements of the Cl(2) absorption cross sections in this region which are vibronically resolved. Laboratory measurements were conducted at four temperatures (298, 273, 233, and 197 K). Spectral modelling of the Cl(2) B(3)Π(0(u)(+))-X(1)Σ(g)(+) electronic transition has been performed, the results of which are in good agreement with our measured spectra.
已经设计和构建了一种双波长范围光谱仪系统，该系统可以在可见光谱的绿光区域同时进行单次通过紫外吸收光谱和腔增强吸收光谱测量。使用该系统，通过同时测量紫外光谱来获得 Cl2 的浓度，对分子氯在 509-570nm 波长范围内的吸收光谱进行了腔增强吸收光谱测量。通过同时测量紫外光谱获得 Cl2 的浓度，得到了该区域内氯吸收截面的绝对值。这些是首次对该区域内的 Cl2 吸收截面进行温度相关测量，并且是振动态分辨的。在四个温度（298、273、233 和 197 K）下进行了实验室测量。对 Cl2 B(3)Π(0(u)(+))-X(1)Σ(g)(+)电子跃迁的 Cl2 光谱进行了建模，结果与我们的测量光谱吻合良好。
