Cavity ring-down spectroscopy of H218O in the range 16570–17120cm−1 (original) (raw)
Journal of Molecular Spectroscopy, 2009
This paper is devoted to the third part of the analysis of the very weak absorption spectrum of the 18O3 isotopologue of ozone recorded by CW-Cavity Ring Down Spectroscopy between 5930 and 6900cm−1. In the two first parts [A. Campargue, A. Liu, S. Kassi, D. Romanini, M.-R. De Backer-Barilly, A. Barbe, E. Starikova, S.A. Tashkun, Vl.G. Tyuterev, J. Mol. Spectrosc. (2009), doi: 10.1016/j.jms.2009.02.012 and E. Starikova, M.-R. De Backer-Barilly, A. Barbe, Vl.G. Tyuterev, A. Campargue, A.W.Liu, S. Kassi, J. Mol. Spectrosc. (2009) doi: 10.1016/j.jms.2009.03.013], the effective operators approach was used to model the spectrum in the 6200–6400 and 5930–6080cm−1 regions, respectively. The analysis of the whole investigated region is completed by the present investigation of the 6490–6900cm−1 upper range. Three sets of interacting states have been treated separately. The first one falls in the 6490–6700cm−1 region, where 1555 rovibrational transitions were assigned to three A-type bands: 3ν2+5ν3, 5ν1+ν2+ν3 and 2ν1+3ν2+3ν3 and one B-type band: ν1+3ν2+4ν3. The corresponding line positions were reproduced with an rms deviation of 18.4×10−3cm−1 by using an effective Hamiltonian (EH) model involving eight vibrational states coupled by resonance interactions. In the highest spectral region – 6700–6900cm−1 – 389 and 183 transitions have been assigned to the ν1+2ν2+5ν3 and 4ν1+3ν2+ν3 A-type bands, respectively. These very weak bands correspond to the most excited upper vibrational states observed so far in ozone. The line positions of the ν1+2ν2+5ν3 band were reproduced with an rms deviation of 7.3×10−3cm−1 by using an EH involving the {(054), (026), (125)} interacting states. The coupling of the (431) upper state with the (502) dark state was needed to account for the observed line positions of the 4ν1+3ν2+ν3 band (rms=5.7×10−3cm−1).The dipole transition moment parameters were determined for the different observed bands. The obtained set of parameters and the experimentally determined energy levels were used to generate a complete line list provided as Supplementary Materials.The results of the analyses of the whole 5930–6900cm−1 spectral region were gathered and used for a comparison of the band centres to their calculated values. The agreement achieved for both 18O3 and 16O3 (average difference on the order of 1cm−1) indicates that the used potential energy surface provides accurate predictions up to a vibrational excitation approaching 80% of the dissociation energy. The comparison of the 18O3 and 16O3 band intensities is also discussed, opening a field of questions concerning the variation of the dipole moments and resonance intensity borrowing by isotopic substitution.
Journal of Quantitative Spectroscopy & Radiative Transfer, 1999
Fourier transform spectra of O-enriched, O-enriched, and natural water vapor recorded between 9600 and 11 400 cm\ have been analyzed to assign the H O spectral lines. More than 1000 transitions were finally assigned to the H O isotopic species leading to 420 precise experimental energy levels of the (0 0 3), (2 0 1), (1 2 1), (1 0 2), (3 0 0), (2 2 0) vibrational states. Rotational, centrifugal distortion, and resonance coupling parameters have been derived from the fit of the experimental energy levels to an effective Hamiltonian based on Pade´-Borel approximants well suited to describe the large centrifugal distortion in H O. The resulting rms deviation is 0.013 cm\ with 97 varied parameters.
Journal of Quantitative Spectroscopy and Radiative Transfer, 2014
This is the third of a series of articles reporting critically evaluated rotationalvibrational 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, H 2 16 O. 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 H 2 16 O from experimentally measured lines, together with their self-consistent uncertainties, for the spectral region up to the first dissociation limit. The spectroscopic network of H 2 16 O contains two components, an ortho (o) and a para (p) one. For o-H 2 16 O and p-H 2 16 O, 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 3000 K recorded in emission, and from multiresonance excitation spectra which sample levels up to dissociation. The total number of transitions considered is 184 667 of which 182 156 are validated: 68 027 between para states and 114 129 ortho ones. These transitions give rise to 18 486 validated energy levels, of which 10 446 and 8040 belong to o-H 2 16 O and p-H 2 16 O, respectively. The energy levels, including their labeling with approximate (J. Tennyson). Journal of Quantitative Spectroscopy & Radiative Transfer 117 (2013) 29-58
Cavity Ring Down Spectroscopy Measurements for High Overtone Vibrational Bands of HC 3 N
The Journal of Physical Chemistry A, 2015
Overtone (5ν 1 and 6ν 1 ) and combination (4ν 1 + ν 3 and 4ν 1 + ν 2 ) vibrational bands of gaseous HC 3 N, located in the visible range (14 600−15 800 and 17 400−18 600 cm −1 ), were investigated by cavity ring-down absorption spectroscopy. The 5ν 1 + ν 3 and 5ν 1 + ν 2 combinations as well as the 6ν 1 + ν 5 − ν 5 hot overtone band have also been identified, on the basis of previous overtone assignments. Absolute integrated intensity values and the ensuing oscillator strengths have been measured here for the first time; f values are typically confined between 4 × 10 −12 and 7 × 10 −11 . For the even weaker 5ν 1 + ν 2 combination band, the oscillator strength was estimated as 9 × 10 −13 . The values concerning CH-stretch overtones (nν 1 ) are similar to those found in the literature for HCN and C 2 H 2 , the molecules with sp-hybridized carbon atoms. Data presented here may prove useful for studying the photochemistry triggered with visible or near-IR radiation within the atmospheres of certain Solar System bodies, including Titan.
Intensity measurements of H216O lines in the spectral region 8000–9350cm−1
Journal of Molecular Spectroscopy, 2010
This paper presents new measurements of H 2 16 O lines performed on spectra recorded with the GSMA Fourier Transform Spectrometer (FTS). Our experimental conditions allow one to obtain new line intensity measurements from 10 À25 to 10 À21 cm/molec at 296 K and self-broadening coefficients in the spectral range centered at 8800 cm À1 . In the HITRAN database, data reported for this region is taken from the work of Mandin et al. (1988) [8,9] and several articles pointed out problems on the line intensities. We present in this paper some intensity comparisons, first with the HITRAN database, and then with the recent article of Tolchenov and Tennyson [3]. We finish by a comparison on self-broadening coefficients.
Journal of Molecular Spectroscopy, 2003
An Intracavity Laser Absorption Spectrometer (ICLAS) based on a Vertical External Cavity Surface Emitting Laser (VECSEL) has been used to record the absorption spectrum of H 2 S between 9540 and 10 000 cm À1 with pressures up to 122 Torr (160.5 hPa) and equivalent absorption path lengths up to 45 km. More than 1600 absorption lines were attributed to the transitions reaching the highly excited ð40 AE ; 0Þ, ð30 AE ; 2Þ, and ð11 þ ; 4Þ states (local mode notation). The existing information relative to the ð40 AE ; 0Þ local mode bright pair at 9911:02 cm À1 was considerably enlarged, while the other states are reported for the first time. Eight hundred and ninety two precise energy levels were derived, including 181 and 28 levels for the H 2 34 S and H 2 33 S minor isotopomers, respectively. These energy levels were fitted using a Watson-type rotational Hamiltonian and the spectroscopic parameters were obtained, yielding an rms deviation of 0:006 cm À1 for the H 2 32 S species-close to the experimental accuracy. The dark states-ð20 þ ; 4Þ and ð11 þ ; 4Þ-at 9647.77 and 9744:88 cm À1 , respectively, were found to perturb the observed energy levels and were then included into the final energy levels modeling. The ð40 AE ; 0Þ states are very close to the local mode limit, i.e., with a mostly identical rotational structure. The ð30 AE ; 2Þ states are separated by 0:077 cm À1 and this separation holds for most of the rotational sublevels. The resonance interactions between the three local mode pairs-ð40 AE ; 0Þ, ð30 AE ; 2Þ, and ð20 AE ; 4Þ-and the ð11 þ ; 4Þ state affect in some cases specifically one of the component of the pair and then the energy separation of the corresponding near degenerate rotational levels. Line intensities were obtained on the basis of the relative intensities measured by ICLAS and from absolute values of the stronger lines measured separately by Fourier Transform Spectroscopy associated with a multipass cell. The transition intensities could be successfully modeled and the integrated band intensities are given and discussed.
This is the second of a series of articles reporting critically evaluated rotationalvibrational 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: HD 16 O, HD 17 O, and HD 18 O. 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, 0-1674, and 0-12 105 cm À 1 for HD 16 O, HD 17 O, and HD 18 O, respectively. For HD 16 O, 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 8818 energy levels. For HD 17 O, only 485 transitions could be analyzed from three sources; the lines correspond to 162 MARVEL energy levels. For HD 18 O, 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 HD 16 O 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 H 2 17 O and H 2 18 O, given in the first paper of this series [Tennyson, et al. J Quant Spectr Rad Transfer 2009;110:573-96], has been updated. a Shift of the middle wavenumber value of the range (new-old). b Indicates that half of the energy levels involved in the transitions in the given source are part of at least this many measured and validated transitions. c This shift is within the original precision of about 0.00006 cm À 1 . d The same calibration factor was determined in . e A very similar calibration factor was determined in . f This is the only ICLAS measurement which was recalibrated as part of the present study.
CW-Cavity Ring Down Spectroscopy of the ozone molecule in the 5980–6220cm−1 region
Journal of Molecular Spectroscopy
The absorption spectrum of ozone, 16 O 3 , has been recorded in the 5980-6220 cm À1 region by high sensitivity CW-Cavity Ring Down Spectroscopy (a min $ 3 · 10 À10 cm À1 ). This study extends a first investigation with the same experimental set-up limited to the 6030-6090 cm À1 spectral region [M.-R. De Backer-Barilly, A. Barbe, Vl.G. Tyuterev, D. Romanini, B. Moeskops, A. Campargue, J. Mol. Struct. 780-781 (2006) 225-233] where the analysis of two A-type bands was reported, using FTS spectra for complementary information. The spectral extension of the recordings allows not only to enlarge considerably the observed transitions of these two bands, but more importantly, to assign four new bands: the 3m 2 + 4m 3 ,5m 1 + m 2 and m 1 + 2m 2 + 4m 3 B-type bands which were considered as dark in our previous report and the 3m 1 + 3m 2 + m 3 A-type band. The high mixing of the observed states approaching the dissociation limit, leads to the breakdown of the polyad structure and ambiguities in the vibrational labelling which are discussed. Finally, 1789 transitions were assigned, and a suitable Hamiltonian model allows reproducing correctly the observations for five of the six observed bands. The list of 1004 experimentally determined energy levels is provided. The determined effective Hamiltonian and transition moment operators were used to generate a list of 5338 transitions given as Supplementary Material. It is interesting to note that the d 5 parameter of the effective transition moment is of great importance to account for the observed intensities of the B-type bands.
Line Position and Line Intensity Modelings of H218O up to the First Triad and J = 20
Journal of Physical and Chemical Reference Data, 2023
Line position and line intensity analyses are carried out for the H218O isotopic species of the water molecule. Both datasets involve the five lowest lying vibrational states. For the line position analysis, the dataset includes infrared and far infrared transitions recorded in this work using high-temperature Fourier transform emission spectroscopy. Also included are already published infrared, far infrared, microwave, terahertz, Doppler-free combination differences, and kHz accuracy lines. The fitting is carried out with the bending–rotation approach and allows us to reproduce 12 858 line positions involving levels with J ≤ 20 and Ka ≤ 18, with a unitless standard deviation of 1.9, varying 207 spectroscopic parameters. For the line intensity analysis, far infrared line intensities measured in this work using Fourier transform spectroscopy in addition to previously measured line intensities are fitted. 5612 line intensities are accounted for with a unitless standard deviation of 1....