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A Fourier Transform (FT) absorption spectrum of room temperature NH 3 in the region 7400 -8600 cm −1 is analysed using a variational line list and ground state energies determined using the MARVEL procedure. The spectrum was measured by Dr Catherine de Bergh in 1980 and is available from the Kitt Peak data center. The centers and intensities of 8468 ammonia lines were retrieved using a multiline fitting procedure. 2474 lines are assigned to 21 bands providing 1692 experimental energies in the range 7000 -9000 cm −1 . The spectrum was assigned by the joint use of the BYTe variational line list and combination differences. The assignments and experimental energies presented in this work are the first for ammonia in the region 7400 -8600 cm −1 , considerably extending the range of known vibrational-excited states.Experimental energies, BYTe, line assignments IntroductionBeing one of the simplest polyatomic molecules and present in many environments, including the interstellar medium, brown dwarfs and solar system planets, NH 3 is a very important molecule for astronomers. It also has several applications in industry, such as the reduction of NOx emissions in smoke stacks [1] and the manufacture of hydrogen cyanide by the Andrussow process [2]. This has motivated over 140 experimental studies on its spectrum, recent work includes high [3, 4, 5, 6] and low [7, 8] temperature studies in various spectral regions. A comprehensive compilation of measured NH 3 rotational and ro-vibrational spectra can be found in a recent MARVEL study [9]. The MARVEL (measured active rotation-vibration energy levels) algorithm [10, 11] simultaneously analyses all available assigned and labelled experimental lines, thus yielding the associated energy levels. The recent study for NH 3 analysed 29,450 measured transitions and yielded 4961 accuratelydetermined energy levels. The critically reviewed and validated high resolu-tion experiments employed by this study, cover the region 0.7 -17,000 cm −1 with a large gap between 7000 -15,000 cm −1 . In fact there is an overall lack of detailed and accurate information for NH 3 transitions in this region.The band model parameters of Irwin et al [12] cover the region 400 to 11000 cm −1 , but was intended for analysis at low spectral resolution so the measurements were obtained at a spectral resolution of only 0.25 cm −1 and not assigned. The HITRAN database [13], a major source of experimental