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Abstract: This is the third of a series of articles reporting critically evaluated rotational–vibrational line positions, transition intensities, and energy levels, with associated critically reviewed labels and uncertainties, for all the main isotopologues of water. This paper presents experimental line positions, experimental-quality energy levels, and validated labels for rotational–vibrational transitions of the most abundant isotopologue of water, H2 16O. The latest version of the MARVEL (Measured Active Rotational–Vibrational Energy Levels) line-inversion procedure is used to determine the rovibrational energy levels of the electronic ground state of H2 16O from experimentally measured lines, together with their self-consistent uncertainties, for the spectral region up to the first dissociation limit. The spectroscopic network of H2 16O containstwo components, an ortho (o) and a para (p) one. For o-H2 16O and p-H2 16O, experimentally measured, assigned, and labeled transitions were analyzed from more than 100 sources. The measured lines come from one-photon spectra recorded at room temperature in absorption, from hot samples with temperatures up to 3000K recorded in emission, and from multiresonance excitation spectra which sample levels up to dissociation. The total number of transitions considered is 184667 of which 182156 are validated: 68027 between para states and 114129 ortho ones. These transitions give rise to 18486 validated energy levels, of which 10446 and 8040 belong to o-H2 16O and p-H2 16O, respectively. The energy levels, including their labeling with approximate normal-mode and rigid-rotor quantum numbers, have been checked against ones determined from accurate variational nuclear motion computations employing exact kinetic energy operators as well as against previous compilations of energy levels. The extensive list of MARVEL lines and levels obtained are deposited in the supplementary data of this paper, as well as in a distributed information system applied to water, W@DIS, where they can easily be retrieved. [Copyright &y& Elsevier]

Abstract: This is the second of a series of articles reporting critically evaluated rotational–vibrational line positions, transition intensities, pressure dependences, and energy levels, with associated critically reviewed assignments and uncertainties, for all the main isotopologues of water. This article presents energy levels and line positions of the following singly deuterated isotopologues of water: HD16O, HD17O, and HD18O. The MARVEL (measured active rotational–vibrational energy levels) procedure is used to determine the levels, the lines, and their self-consistent uncertainties for the spectral regions 0–22708, 0–1674, and 0–12105cm−1 for HD16O, HD17O, and HD18O, respectively. For HD16O, 54740 transitions were analyzed from 76 sources, the lines come from spectra recorded both at room temperature and from hot samples. These lines correspond to 36690 distinct assignments and 8818 energy levels. For HD17O, only 485 transitions could be analyzed from three sources; the lines correspond to 162 MARVEL energy levels. For HD18O, 8729 transitions were analyzed from 11 sources and these lines correspond to 1864 energy levels. The energy levels are checked against ones determined from accurate variational nuclear motion computations employing exact kinetic energy operators. This comparison shows that the measured transitions account for about 86% of the anticipated absorbance of HD16O at 296K and that the transitions predicted by the MARVEL energy levels account for essentially all the remaining absorbance. The extensive list of MARVEL lines and levels obtained are given in the Supplementary Material of this article, as well as in a distributed information system applied to water, W@DIS, where they can easily be retrieved. In addition, the transition and energy level information for H2 17O and H2 18O, given in the first paper of this series [Tennyson, et al. J Quant Spectr Rad Transfer 2009;110:573–96], has been updated. [Copyright &y& Elsevier]

Abstract: This is the first part of a series of articles reporting critically evaluated rotational–vibrational line positions, transition intensities, pressure dependence and energy levels, with associated critically reviewed assignments and uncertainties, for all the main isotopologues of water. The present article contains energy levels and data for line positions of the singly substituted isotopologues H2 17Oand H2 18O. The procedure and code MARVEL, standing for measured active rotational–vibrational energy levels, is used extensively in all stages of determining the validated levels and lines and their self-consistent uncertainties. The spectral regions covered for both isotopologues H2 17O and H2 18O are . The energy levels are checked against ones determined from accurate variational calculations. The number of critically evaluated and recommended levels and lines are, respectively, 2687 and 8614 for H2 17O, and 4839 and 29364 for H2 18O. The extensive lists of MARVEL lines and levels obtained are deposited in the Supplementary Material, as well as in a distributed information system applied to water, W@DIS, where they can easily be retrieved. A distinguishing feature of the present evaluation of water spectroscopic data is the systematic use of all available experimental data and validation by first-principles theoretical calculations. [Copyright &y& Elsevier]