A spectroscopic study of water vapor isotopologues (H2OH2O)-O-16-O-18 and HDO using a continuous wave DFB quantum cascade laser in the 6.7 mu m region for atmospheric applications

摘要

A quantum cascade spectrometer was used in the laboratory to study H-2 O-16, (H2O)-O-18 and HDO line intensities near 6.7 mu m. The spectral region ranging from 1483 to 1487 cm(-1), which is suitable for the in situ laser sensing of these isotopologues in the atmosphere, was investigated using a continuous-wave distributed feed-back quantum cascade laser. Eight lines of water vapor isopologues were studied-one line of the nu(2) band of H-2 O-16, one line of the 2 nu(2)-nu(2) band of (H2O)-O-16, two lines of the nu(2) band of (H2O)-O-18 and four lines of the nu(2) band of HDO were carefully revisited. The measured intensities were thoroughly compared to relevant molecular databases and other experimental and calculated results. We also observe that the H2O, D2O, HDO equilibrium constant agrees excellently with previously determined values. (C) 2005 Elsevier Ltd. All rights reserved.