Ammonia line strengths and N2-, O2-, Ar-, He-, and self-broadening coefficients in the v2 band near 10.4 μm

Scanning-wavelength laser absorption measurements were carried out to determine the line strengths and broadening coefficients due to collisions of N-2 , O-2 , Ar, He, and NH3 for 12 ammonia transitions in the Q-branch of the v(2) fundamental band near 10.4 mu m. The measurements were conducted at 296 K using a high-resolution quantum cascade laser and span the frequency range of 957.5-963.0 cm(-1). The absorption features were fitted with a Voigt profile to obtain the spectroscopic parameters. The temperature dependence of the Ar-broadening coefficients for two transitions, suitable for high-temperature NH3 detection, were measured using a shock tube for the temperature range of 921-1767 K. The reported spectroscopic parameters are useful for developing NH3 detection sensors, especially for high-temperature applications involving chemical reactions. (C) 2021 Elsevier Ltd. All rights reserved.

Automated summary

Scanning-wavelength laser absorption measurements were conducted to determine line strengths and broadening coefficients of ammonia transitions in the Q-branch of the v(2) fundamental band. The spectroscopic parameters obtained are useful for developing NH3 detection sensors, especially for high-temperature applications.