The ammonia absorption spectrum between 4700 and 5650 cm −1

International audienceRoom temperature absorption spectra of ammonia were recorded by high-resolution Fourier transform spectroscopy in the 4700-5600 cm −1 range at four pressures (13, 46, 140, and 304 Pa). Additionally, we use an existing Kitt Peak spectrum to extend the analysis up to 5650 cm −1. In total, 9110 absorption lines with intensity ranging from 1 × 10 −25 to 1.6 × 10 −20 cm/molecule were retrieved, for the two principal isotopologues. Another Kitt Peak spectrum was used to identify 505 15 NH 3 transitions within the experimental line list. The rovibrational assignments of the 14 NH 3 lines relied on the position and intensity agreement with the C2018 theoretical line list (Coles et al. JQSRT 2018;219 199-212) and were validated by the systematic use of Lower State Combination Difference (LSCD) relations. In the process, a number of intensity transfer between nearby transitions were identified. Finally, 6562 transitions were assigned to 61 vibrational bands of the main isotopologue, 14 NH 3 , representing over 99.8% of the C2018 integrated absorption at room temperature in the region. The upper state empirical energy of a total of 2215 rovibrational levels of 14 NH 3 were derived. Most of them are newly reported. The comparison with the current HITRAN2020 list is discussed. A recommended line list for ammonia in natural isotopic abundance is provided for the studied region