A collaborative 14NH3 IR spectroscopic analysis at 6000 cm−1

• Laboratory measurement and theoretical analysis for 14 NH 3 IR spectra in 5600–6300 cm −1 . Assigned definitive rovibrational quantum numbers to 1602 transitions pertaining 809 upper levels eight vibrational bands. Good h eff models. The JPL+Ames (JA) line list reports 87 new lines 179 assignments. Other assignments agree with Cacciani et al. 1278 transitions. Band-by-band quality check uses the δΕ δΔ consistency analysis. Ames HSL-Pre3 positions are still more accurate than C2018 this range. JA lists of reported supplementary files. We report results from combined efforts laboratory measurements region, based on Kitt Peak previously used study 6300–7000 region [Sung al., JQSRT 2012, 113:1066]. Definitive were assigned bands: 0111 E , A 1101, 0310, 0211, 1300, 0103 0302. When compared [JQSRT 2020, 258:107,334], our results, termed as “JPL+Ames 2021” (or list), showed good agreement assignment have further made that not their work, plus first time. Excellent (± 0.002 ) was observed between work no systematic discrepancies. Remaining discrepancies been attributed blendings, unaccounted resonances, uncertainties reference lists, limited transition-matching accuracy. An empirical (JPL) a semi-empirical adopting UCL-C2018 [Coles 2018, 219:199] intensity employed major In addition position / cross-validation through combination difference analysis, part has also required manual matches valid transition level pairs checking patterns Calc-Obs inversion splittings Δ a-s etc. discussions presented missing ν 2 +3ν 4 (0103), unusual sensitivity 1 (1300) s levels, borrowed 6ν (0600), potential outliers +ν (1101), These will be topics future work.