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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 Preprint submitted to Journal of Quantitative Spectroscopy & Radiative Transfer10th June 2010 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 0–22 708, 0–1 674, and 0–12 105 cm−1 for HD16O, HD17O, and HD18O, respectively. For HD16O, 54 740 transitions were analyzed from 76 sources, the lines come from spectra recorded both at room temperature and from hot samples. These lines correspond to 36 690 distinct assignments and 8 818 energy levels. For HD17O, only 485 transitions could be analyzed from 3 sources; the lines correspond to 162 MARVEL energy levels. For HD18O, 8 729 transitions were analyzed from 11 sources and these lines correspond to 1 860 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 296 K 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 [J. Quant. Spectr. Rad. Transfer 110 (2009) 573-596], has been updated. Key words: Water vapor, transition wavenumbers, atmospheric physics, energy levels, MARVEL, information system, database, W@DIS, infrared spectra, microwave spectra, HD16O, HD17O, HD18O

The present analysis substantially improves the spectroscopic characterization of near infrared OCS in a window region (3850–4200 cm−1) important for atmospheric studies of Venus. Previous studies in this spectral region cataloged numerous OCS line positions, but accurate line intensities were measured for only three strong bands. In this paper, the corresponding line intensities are obtained for 41 OCS bands, including weak isotopic bands reported for the first time. The 2ν3 (0002–0000) band is analyzed for 10 OCS isotopologues (adding 16O13C34S, 17O12C32S, 16O12C36S, 18O12C34S, and 16O13C33S). In addition, observations of 0332–0330 of the main isotope, 16O12C32S, provides accurate vibration–rotation parameters for the upper state (and the lower state, 0330 of 16O12C32S). Finally, one unidentified band is seen at 3969.3 cm−1; its lower state is clearly the ground state of 16O12C32S. The line strengths of these seven previously unanalyzed bands plus 34 other bands of the OCS isotopologues, 16O12C32S, 16O12C34S, 16O13C32S, 16O12C33S, and 18O12C32S, were least-squares fitted to determine strength parameters, Sv and Herman-Wallis coefficients. Finally, the intensities of 17 additional very weak bands were estimated to provide an extensive new database of OCS line parameters to support remote sensing of Venus. The integrated intensity in cm−1/(molecule cm−2) at 296 K is 8.1×10−19 for the 3800–4200 cm−1 region.

To support planetary studies of the Venus atmosphere, we measured line strengths of the 2 v 3 , v 1 +2 v 2 + v 3 , and 4 v 2 + v 3 bands of the primary isotopologue of carbonyl sulfide ( 16 O 12 C 32 S), whose band centers are located at 4101.387, 3937.427, and 4141.212 cm −1 , respectively. For this, infrared absorption spectra in normal carbonyl sulfide (OCS) sample gas were recorded at an unapodized resolution of 0.0033 cm −1 at ambient room temperatures using a Bruker Fourier transform spectrometer (FTS) at the Jet Propulsion Laboratory. The FTS instrumental line shape (ILS) function was investigated, which revealed no significant instrumental line broadening or distortions. Various custom-made short cells and a multi-pass White cell were employed to achieve optical densities sufficient to observe the strong 2 v 3 and the weaker bands in the region. Gas sample impurities and the isotopic abundances were determined from mass spectrum analysis. Line strengths were retrieved spectrum by spectrum using a non-linear curve fitting algorithm adopting a standard Voigt line profile, from which Herman–Wallis factors were derived for the three bands. The band strengths of 2 v 3 , v 1 +2 v 2 + v 3 , and 4 v 2 + v 3 of 16 O 12 C 32 S (normalized at 100% of isotopologue) are observed to be 6.315(13)×10 −19 , 1.570(2)×10 −20 , and 7.949(20)×10 −21 cm −1 /molecule cm −2 , respectively, at 296 K. These results are compared with earlier measurements and the HITRAN 2004 database.

A new spectroscopic database for carbon dioxide in the near infrared is presented to support remote sensing of the terrestrial planets (Mars, Venus and the Earth). The compilation contains over 28,500 transitions of 210 bands from 4300 to 7000 cm−1 and involves nine isotopologues: 16O12C16O (626), 16O13C16O (636), 16O12C18O (628), 16O12C17O (627), 16O13C18O (638), 16O13C17O (637), 18O12C18O (828), 17O12C18O (728) and 18O13C18O (838). Calculated line positions, line intensities, Lorentz half-width and pressure-induced shift coefficients for self- and air-broadening are taken from our recent measurements and are presented for the Voigt molecular line shape. The database includes line intensities for 108 bands measured using the McMath–Pierce Fourier transform spectrometer located on Kitt Peak, Arizona. The available broadening parameters (half-widths and pressure-induced shifts) of 16O12C16O are applied to all isotopologues. Broadening coefficients are computed using empirical expressions that have been fitted to the experimental data. There are limited data for the temperature dependence of widths and so no improvement has been made for those parameters. The line intensities included in the catalog vary from 4×10−30 to 1.29×10−21 cm−1/(molecule cm−2) at 296 K. The total integrated intensity for this spectral interval is 5.9559×10−20 cm−1/(molecule cm−2) at 296 K.

The temperature dependence of air-broadened halfwidths are reported for some 500 transitions in the (000)-(000) and (010)-(000) bands of H2(16)O using gas sample temperatures ranging from 241 to 388 K. These observations were obtained from infrared laboratory spectra recorded at 0.006 to 0.011 cm(exp-1) resolution with the McMath-Pierce Fourier transform spectrometer located at Kitt Peak. The experimental values of the temperature dependence exponents, eta, were grouped into eight subsets and fitted to empirical functions in a semi-global procedure. Overall, the values of eta were found to decrease with increasing rotational quantum number J. The number of measurements (over 2200) and transitions (586) involved exceeds by a large margin that of any other comparable reported study.

High-resolution spectra of H 2 O were recorded with the McMath Fourier-transform spectrometer at the National Solar Observatory located at Kitt Peak, AZ. Seventeen laboratory spectra of water plus air mixtures were recorded at a spectral resolution of 0.01 cm - 1 covering the region between 2800 and 8000 cm - 1 . Over 4000 linewidth and pressure-induced frequency shift coefficients were derived from the spectral data with sample temperatures near or at room temperature (296 K). The measurements include transitions of H2 16O, H2 17O, and H2 18O with the rare oxygen species observed in normal H 2 O gas samples. The measurements were analyzed with consideration of collision-narrowing effects. The analysis required a knowledge of the self-broadened linewidth coefficients, and the data measured and reported in the previous study were used along with earlier results for this purpose. The self-broadened and air-broadened measured linewidth coefficients obtained here as well as those reported in earlier studies covering the 600–2400 cm - 1 , were fitted to an empirical expression which contains up to 28 terms. Two fitting procedures were used: one considered the fit of families of transitions and the other was more global in scope. The computed linewidth coefficients derived from the fitted parameters are compared statistically to measurements in this work as well as other studies.

High-resolution spectra of H 2 O were recorded with a Fourier-transform spectrometer covering H 2 O transitions from 2900 to 8000 cm −1 . Over 13,000 absorptions were measured to determine line positions, strengths and self-broadened half-width coefficients. The H 2 16 O line strengths of the (0 3 0)–(0 1 0), (1 1 0)–(0 1 0), (0 1 1)–(0 1 0) and (0 3 0)–(0 0 0), (1 1 0)–(0 0 0), (0 1 1)–(0 0 0) bands were fitted to a quantum mechanical model which involves the interactions between the (0 3 0), (1 1 0), and (0 1 1) vibrational states. Also fitted were experimental strengths of the hot bands; (1 2 0)–(0 1 0) and (0 2 1)–(0 1 0). The model includes 14 dipole matrix elements for B- and A-type transitions. The measured line positions were used along with hot water emission measurements (for the (0 3 0), (0 4 0), and (0 5 0) states of H 2 16 O) in an analysis to obtain high-accuracy energy level values in the (0 3 0), (1 1 0), (0 1 1), (0 4 0), (1 2 0), (0 2 1), (2 0 0), (1 0 1), (0 0 2), and (0 5 0) vibrational states of H 2 16 O and the (1 1 0) and (0 1 1) states of H 2 17 O. Also included were measurements and analysis of self-broadened half-widths for over 4700 absorptions between 4405 and 7729 cm −1 . The results from this investigation provide new information for the noted H 2 17 O bands and present a more accurate representation of the measured H 2 16 O bands.

This paper describes the status circa 2001, of the HITRAN compilation that comprises the public edition available through 2001. The HITRAN compilation consists of several components useful for radiative transfer calculation codes: high-resolution spectroscopic parameters of molecules in the gas phase, absorption cross-sections for molecules with very dense spectral features, aerosol refractive indices, ultraviolet line-by-line parameters and absorption cross-sections, and associated database management software. The line-by-line portion of the database contains spectroscopic parameters for 38 molecules and their isotopologues and isotopomers suitable for calculating atmospheric transmission and radiance properties. Many more molecular species are presented in the infrared cross-section data than in the previous edition, especially the chlorofluorocarbons and their replacement gases. There is now sufficient representation so that quasi-quantitative simulations can be obtained with the standard radiance codes. In addition to the description and justification of new or modified data that have been incorporated since the last edition of HITRAN (1996), future modifications are indicated for cases considered to have a significant impact on remote-sensing experiments. (C) 2003 Elsevier Ltd. All rights reserved.

This experimental study reports self-broadened linewidths and pressure-induced frequency-shifts of water vapor in the spectral region between 590 and 2400 cm−1. Over 1900 vibration–rotation transitions have been measured at 0.0054 cm−1 resolution using the Fourier transform spectrometer at Kitt Peak National Observatory. Self-broadening parameters have been obtained for the (000)–(000), (010)–(010), (010)–(000), (020)–(010), and (100)–(010) vibrational bands of H216O, H218O, and H217O. The observed widths range from 0.52 to 0.1 cm−1 atm−1, and the pressure shifts fall between ±0.05 cm−1 atm−1. The present linewidth coefficients are compared with previously measured and computed values given in the available literature. There have been no prior studies of self-broadened frequency-shifts of water vapor lines of this spectral region.

We describe in this paper the modifications, improvements, and enhancements to the HITRAN molecular absorption database that have occurred in the two editions of 1991 and 1992. The current database includes line parameters for 31 species and their isotopomers that are significant for terrestrial atmospheric studies. This line-by-line portion of HITRAN presently contains about 709,000 transitions between 0 and 23,000/cm and contains three molecules not present in earlier versions: COF2, SF6, and H2S. The HITRAN compilation has substantially more information on chlorofluorocarbons and other molecular species that exhibit dense spectra which are not amenable to line-by-line representation. The user access of the database has been advanced, and new media forms are now available for use on personal computers.

Measurements of the strengths and air-broadened widths of 223 lines of water vapor have been made with high resolution in the region 2950–3400 cm-1. The strength data of the lines in the 2ν2 and ν1 bands are analyzed to determine the band strengths and the coefficients of the F factors. The band strengths of the 2ν2 and ν1 bands were found to be 1.75±0.08 and 10.3±1.1 cm-2 atm-1 at 296 K, respectively. The selection rules of the lines observed in the ν3 band are forbidden in the symmetric-rotor limit. The majority of the measured strengths of these lines differ from the calculated values because of different asymmetries in the upper and lower vibrational states. Also, Coriolis perturbations in several lines of the ν1 and ν3 bands were observed in the strength measurements. The direct method was applied to determine the air-broadened line widths. The results are compared to the computed values of Benedict and Kaplan. There is good agreement between this work and the computed results for line width values greater than 0.05 cm-1 atm-1. However, for line widths less than 0.05 cm-1 atm-1, the measured values are smaller than the computed widths. A value of 0.018 cm-1 atm-1 is given for the width of the line at 3378.071 cm-1, whereas the calculated value is 0.032 cm-1 atm.

Measurements of the strengths of 311 lines of water vapor have been made with high resolution in the region 5000–5750 cm -1 . The strength data of lines in the (011) and (110) bands are analyzed to determine the band strengths and the coefficients of the F factors. The band strengths of the (011) and (110) bands were found to be 20.65±0.21 and 0.384±0.015 cm -2 atm -1 at 296 K, respectively. Many of the measured strengths in the (011) and (110) bands differ from the calculated values because of strong Coriolis interactions. Also included in the present work are measurements of strengths of four lines in the (030) band and 36 lines in the “hot” band (021)-(010).