Study of H216O and H218O absorption in the 16,460-17,200 cm-1 range using LED-based Fourier transform spectroscopy

The spectra of the (H2O)-O-16 and (H2O)-O-18 vapor have been recorded between 16,460 and 17,200 cm(-1) by a Fourier transform spectrometer with spectral resolution of 0.05 cm(-1) using high luminance LED light source and 60 cm multipath cell with a path length of 3480 cm. A high signal-to-noise ratio (S/N approximate to 5000) enable us to register the lines with intensities of 1.54 x 10(-24) to 2.0 x 10(-27) cm/molecule. More than 1300 lines were recorded in the spectrum of the natural abundance water vapor and over 1800 lines in the spectrum of the vapor enriched by O-18. 422 rotation-vibration energy levels of the (H2O)-O-18 molecule have been assigned to twenty vibrational states. The majority of these energies was attributed to the (241), (321), (340), (420), (401), (500), and (123) states. 43 energy levels were tentatively assigned to the (043), (142), (302), (161), (260), and (062) states. Eleven energy levels were labeled as belonging to the (280), (081), (190), (0 10 0), (1 10 0), (0 11 0), and (0 12 0) states. The recorded spectra were compared with the simulations based on the HITRAN2016 database and variational lists. (C) 2018 Elsevier Ltd. All rights reserved.