The cavity-enhanced absorption spectrum of NH3 in the near-infrared region between 6850 and 7000 cm−1

In this paper, we describe new high-resolution measurements of the absorption spectrum of 14NH3 in the 6850-7000 cm−1 region using cavity-enhanced absorption spectroscopy (CEAS), and Fourier-transform spectroscopy (FTS) between ∼6400 and 6900 cm−1. The CEAS measurements were used to determine line positions, line intensities (cross-sections) and pressure-broadening parameters, the latter in three different bath gases. A total of 1117 NH3 lines were observed. The accuracy of the line positions is about 0.001 cm−1, and absorptions cross-sections as low as 1×10−23 cm2 molecule−1 are reported.