Fourier-transform absorption spectroscopy of H218O in the first hexade region

The Fourier-transform absorption spectrum of H218O was recorded in the 6000-7940 cm−1 region and assigned on the base of the very accurate ab initio calculations by Partridge and Schwenke (PS) [J. Chem. Phys. 106 (1997) 4618-4639; J. Chem. Phys. 113 (2000) 6592-6597]. A set of 821 accurate rovibrational energy levels was obtained for six interacting states of the first hexad: (101), (120), (021), (200), (002), and (040). 290 of them are reported for the first time. The experimental line intensities are also estimated and compared with the PS calculations and the available literature data in the considered spectral range.