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In a companion paper, rovibrational assignments of acetylene in the 9280–10,740 cm –1 region were extended on the basis of a long path absorption spectrum recorded by Fourier-transform spectroscopy. Thirty-three and seven bands of 12 C 2 H 2 and 12 C 13 CH 2 were assigned, respectively, twelve 12 C 2 H 2 bands being newly assigned. In the present work, the vibrational transition dipole moments squared and Herman–Wallis coefficients of the bands are derived from a fit of the measured intensity values. An empirical recommended line list is provided with positions calculated using empirical spectroscopic band parameters and intensities calculated using the derived Herman–Wallis coefficients. As a result the constructed line list in the 9450–10,740 cm -1 region includes a total of 2774 lines belonging to 32 bands of 12 C 2 H 2 and seven bands of 12 C 13 CH 2 . For comparison the HITRAN database in the same region includes 305 lines of 4 bands, all belonging to 12 C 2 H 2 . The recommended acetylene line list is compared to the HITRAN line list and to the Acetylene Spectroscopic Database (ASD) constructed using the global effective operator approach. The measured bands belong to the ΔP  = 15 and 16 series of bands where P  = 5 V 1  + 3 V 2  + 5 V 3  +  V 4  +  V 5 is the polyad quantum number. An improved set of ΔP  = 15 effective dipole moment (EDM) parameters is derived from a fit of the measured intensity values. The ΔP  = 16 EDM parameters are derived for the first time. The derived sets of EDM will allow extending the Acetylene Spectroscopic Database at higher energy. [ABSTRACT FROM AUTHOR]

The high-resolution absorption spectrum of acetylene is studied by Fourier-transform spectroscopy (FTS) in the 9280–10740 cm –1 region dominated by the 3ν 3 band near 9640 cm −1 . Line positions and intensities of 1899 12 C 2 H 2 and 151 12 C 13 CH 2 absorption lines are retrieved from a spectrum recorded at room temperature (298.5 K) with a pressure of 87.6 hPa and a path length of 105 m. The measured 12 C 2 H 2 lines belong to thirty-three bands, twelve of them being newly assigned. The lines of 12 C 13 CH 2 in normal abundance (2.2%) belong to seven bands. For comparison the HITRAN database in the same region includes 301 lines of four 12 C 2 H 2 bands. Spectroscopic parameters of the upper vibrational levels are derived from band-by-band fits of the line positions (typical rms values are on the order of 0.002 cm –1 ). The comparison to the HITRAN line list and to results obtained using the global effective operator approach reveals a number of significant deviations. The occurrence of local rovibrational perturbations affecting a number of the analyzed bands is illustrated by the case of the strong 3ν 3 band. [ABSTRACT FROM AUTHOR]

Six studies have been recently devoted to a systematic analysis of the high-resolution near infrared absorption spectrum of acetylene recorded by Cavity Ring Down spectroscopy (CRDS) in Grenoble and by Fourier-transform spectroscopy (FTS) in Brussels and Hefei. On the basis of these works, in the present contribution, we construct an empirical database for acetylene in the 5850–9415 cm –1 region excluding the 6341–7000 cm −1 interval corresponding to the very strong ν 1 +ν 3 manifold. Our database gathers and extends information included in our CRDS and FTS studies. In particular, the intensities of about 1700 lines measured by CRDS in the 7244–7920 cm −1 region are reported for the first time together with those of several bands of 12 C 13 CH 2 present in natural isotopic abundance in the acetylene sample. The Herman-Wallis coefficients of most of the bands are derived from a fit of the measured intensity values. A recommended line list is provided with positions calculated using empirical spectroscopic parameters of the lower and upper energy vibrational levels and intensities calculated using the derived Herman-Wallis coefficients. This approach allows completing the experimental list by adding missing lines and improving poorly determined positions and intensities. As a result the constructed line list includes a total of 11113 transitions belonging to 150 bands of 12 C 2 H 2 and 29 bands of 12 C 13 CH 2 . For comparison the HITRAN database in the same region includes 869 transitions of 14 bands, all belonging to 12 C 2 H 2 . Our weakest lines have an intensity on the order of 10 –29 cm/molecule, about three orders of magnitude smaller than the HITRAN intensity cut off. Line profile parameters are added to the line list which is provided in HITRAN format. The comparison of the acetylene database to the HITRAN2012 line list or to results obtained using the global effective operator approach is discussed in terms of completeness and accuracy. [ABSTRACT FROM AUTHOR]

The absorption spectrum of acetylene is studied by high-resolution Fourier-transform spectroscopy (FTS) between 8980 and 9420 cm –1 . Positions and intensities of 432 1 2 C 2 H 2 absorption lines are retrieved from a spectrum recorded at room temperature (298.5 K) with a pressure of 87.6 hPa and a 105 m path length. The measured lines belong to 11 bands including three bands observed for the first time. The obtained intensity dataset constitutes the first intensity information in the region. The Herman-Wallis coefficients are derived from a fit of the measured intensity values. The reported results will be valuable to complete the spectroscopic databases of acetylene. [ABSTRACT FROM AUTHOR]

The absorption spectrum of acetylene has been recorded at room temperature (296 K) using high sensitivity Cavity Ring Down Spectroscopy in the 7914 and 8252 cm −1 interval. The noise equivalent absorption of the spectra is α min ∼ 5×10 −11 cm −1 . A list of about 5600 absorption features was constructed. The smallest intensities are on the order of 10 −29 cm/molecule. A total of 1325 rovibrational lines of 12 C 2 H 2 were assigned by comparison with accurate predictions provided by a global effective operator model. In addition, 132 rovibrational lines of 12 C 13 CH 2 present in natural isotopic abundance were assigned on the basis of their published positions. The assigned 12 C 2 H 2 lines belong to 12 new and 6 already known bands, for which additional J -lines were assigned. The line intensities of the three cold bands of 12 C 13 CH 2 are reported for the first time. The new data will be valuable to refine the parameters of the global effective Hamiltonian and dipole moments of 12 C 2 H 2 in the region. Spectroscopic parameters of the 12 C 2 H 2 and 12 C 13 CH 2 upper vibrational levels were derived from a band-by-band fit of the line positions (typical rms values are on the order of 0.001 cm −1 ). A few of the analyzed bands were found to be affected by rovibrational perturbations, which are discussed. In particular, the rotational structure of the 2 ν 1 + ( ν 4 + ν 5 ) 0 Σ u + –Σ g + band near 7994 cm −1 exhibits a particularly surprising intensity distribution: while the P (19) and R (17) transitions share the same J = 18 upper level, the R (17) line has an intensity about 4 orders of magnitude smaller than the P (19) line. This unusual situation is quantitatively interpreted as resulting from a Coriolis interaction between the ν 1 + 2 ν 2 + ν 5 1 and 2 ν 1 + ( ν 4 + ν 5 ) 0 bands with a energy crossing at J = 18. The accidental nearly perfect cancelation of the two terms contributing to the line strength of the R (17) line leads to the near disappearance of this line. [ABSTRACT FROM AUTHOR]

High resolution (0.011 cm –1 ) room temperature (295 K) Fourier transform absorption spectra (FTS) of acetylene have been analyzed in the 8280–8700 cm −1 range dominated by the ν 1 + ν 2 + ν 3 band at 8512 cm −1 . Line positions and intensities were retrieved from FTS spectra recorded at 3.84 and 56.6 hPa. As a result, a list of 1001 lines was constructed with intensities ranging between about 2×10 −26 and 10 −22 cm/molecule. Comparison with accurate predictions provided by a global effective operator model led to the assignment of 629 12 C 2 H 2 lines. In addition, 114 lines of the 13 C 12 CH 2 isotopologue were assigned using information available in the literature. The 12 C 2 H 2 lines belong to thirteen bands, nine of which being newly reported. The 13 C 12 CH 2 lines belong to three bands, the intensities of which being reported for the first time. Spectroscopic parameters of the 12 C 2 H 2 upper vibrational levels were derived from band-by-band analyses of the line positions (typical rms are on the order of 0.002 cm −1 ). Three of the analyzed bands were found to be affected by rovibrational perturbations, which are discussed in the frame of a global effective Hamiltonian. The obtained line parameters are compared with those of the two bands included in the HITRAN 2012 database. [ABSTRACT FROM AUTHOR]

High resolution (0.011 cm –1 ) room temperature (295 K) Fourier transform absorption spectra (FTS) of acetylene have been recorded between 7000 and 7500 cm –1 . Line parameters (positions, intensities and self broadening coefficients) have been measured using a multispectrum treatment of three FTS spectra, recorded at 3.84, 8.04 and 56.6 hPa. As a result, a list of 3788 lines was constructed with intensities ranging between about 10 –26 and 10 –22 cm/molecule. Comparison with accurate predictions provided by a global effective operator model (Lyulin OM, Perevalov VI, Teffo JL, Proc. SPIE 2004;5311:134–43) led to the assignment of 2471 of these lines to 12 C 2 H 2 . The assigned lines belong to 29 12 C 2 H 2 bands, 12 of them being newly reported. Spectroscopic parameters of the upper vibrational levels were derived from band-by-band fits of the line positions (typical rms values are on the order of 0.001 cm –1 ). About half of the analyzed bands were found to be affected by rovibrational perturbations. Line parameters obtained in this work were compared with those available for about 350 transitions in the HITRAN 2012 database. The large set of new data will be valuable to refine the parameters of the global effective Hamiltonian and dipole moments of 12 C 2 H 2 . [ABSTRACT FROM AUTHOR]

The absorption spectrum of acetylene has been recorded at room temperature (297 K) using high-sensitivity cavity ring-down spectroscopy (αmin∼ 5×10−11cm−1) in the 5851 and 6341 cm−1interval corresponding to a region of very weak absorption. A list of about 10,700 absorption features with estimated absolute line intensities was constructed. The smallest intensities are of the order of 5×10−29cm molecule−1. The line list includes about 2500 absorption lines of ethylene present at the ppm level in the acetylene sample and identified on the basis of a high-resolution Fourier transform spectrum specifically recorded. A total of more than 2700 lines of12C2H2were rovibrationally assigned in comparison with accurate predictions provided by a global effective operator model. Overall, the present effort adds about 2260 new assignments to the set of about 500 assigned transitions available in the literature. The new assignments correspond to 45 new bands and 17 already-known bands, for which additionalJlines were assigned. Spectroscopic parameters were derived for the upper vibrational levels from a band by band fit of the line positions (typical root mean square deviation values are of the order of 0.001 cm−1). A few of the analysed bands were found to be affected by rovibrational perturbations, which are discussed. The new data will be valuable to refine the parameters of the global effective Hamiltonian and dipole moments of12C2H2. [ABSTRACT FROM PUBLISHER]

Abstract: The absorption spectrum of acetylene has been recorded using high sensitivity cavity ring down spectroscopy (α min ~5×10−11 cm−1) in the 7244–7918cm−1 interval corresponding to a weak absorption region. The CRDS spectra revealed new bands which were identified on the basis of a global effective Hamiltonian model (Lyulin OM, Perevalov VI, Teffo JL. Proc. SPIE 2004;5311:134–43). Overall, about 2100 lines were rovibrationally assigned in the investigated interval. They belong to 26 new bands and to the eight already known bands of the region, for which additional J-lines were assigned. The spectroscopic parameters were derived from a band by band fit of the line positions. Part of the analyzed bands was found affected by strong rovibrational perturbations which are discussed. These new data will be valuable to refine the global effective Hamiltonian of 12C2H2 at higher energy. [Copyright &y& Elsevier]

Abstract: The assignment of the high resolution Fourier transform spectra of carbon dioxide enriched in 17O and 18O which were recorded in LADIR (Paris, France) with the Bruker IFS 125-HR between 1800 and 9000cm−1 and in USTC (Hefei, China) with the Bruker IFS 120-HR between 1700 and 9000cm−1 was performed. In total 239 bands of 12 isotopologues: 16O12C16O, 16O12C18O, 16O13C16O, 16O13C18O, 18O12C18O, 18O13C18O, 16O12C17O, 17O12C17O, 17O12C18O, 16O13C17O, 17O13C17O and 17O13C18O were observed. Among them, 99 bands were observed for the first time. The majority of new observed bands belong to 17OCO isotopologues. The positions of 23,003 lines were determined with the experimental uncertainty on the level of 0.001cm−1. The spectroscopic constants were fitted to the observed line positions for all observed bands. [Copyright &y& Elsevier]

Abstract: The high resolution absorption spectra of 13CH4 were recorded at 81K by differential absorption spectroscopy using a cryogenic cell and a series of distributed feed back (DFB) diode lasers and at room temperature by Fourier transform spectroscopy. The investigated spectral region corresponds to the high energy part of the 13CH4 tetradecad dominated by the 2ν 3 overtone near 5988cm−1. Empirical line lists were constructed containing, respectively, 1629 13CH4 transitions detected at 81K (5852–6124cm−1) and 3481 features (including 85 lines of 12CH4) measured at room temperature (5850–6150cm−1); the smallest measured intensities are about 3×10−26 and 4×10−25 cm/molecule at 81 and 296K, respectively. The lower state energy values were derived for 1196 13CH4 transitions from the variation of the line intensities between 81 and 296K. These transitions represent 99.2% and 84.6% of the total absorbance in the region, at 81 and 296K, respectively. Over 400 additional weak features were measured at 81K and could not be matched to lines observed at room temperature. The quality of the resulting empirical low energy values is demonstrated by the excellent agreement with the already-assigned transitions and the clear propensity of the empirical low J values to be close to integers. The two line lists at 81 and at 296K provided as will enable future theoretical analyses of the upper 13CH4 tetradecad. [Copyright &y& Elsevier]

The method of effective operators has been applied to the global fitting of line intensities of the acetylene molecule in the middle infrared. Simultaneous fittings of recently observed line intensities in the cold and hot bands lying in the 13.6, 7.8, and 5 μm regions have been performed. The eigenfunctions of the effective Hamiltonian developed for the global treatment of the vibration–rotation line positions of acetylene [O.M. Lyulin, V.I. Perevalov, S.A. Tashkun, J.-L. Teffo, in: Leonid N. Sinitsa (Ed.), 13th Symposium and School on High Resolution Molecular Spectroscopy, Proceedings of SPIE, vol. 4063, 2000, pp. 126–133] have been used in the calculations. The sets of effective dipole moment parameters obtained reproduce the observed line intensities within the experimental accuracy. The importance of l-type resonance, responsible for some large differences between intensities of the same lines in subbands having opposite parities, is exhibited and discussed. [Copyright &y& Elsevier]

• A high sensitivity absorption spectrum of acetylene is recorded by CRDS near 1.2 µm. • More than 2600 lines are assigned to a total of 52 bands of 12C 2 H 2 , 12C13CH 2 and 12C 2 HD. • Spectroscopic parameters and Herman-Wallis coefficients are derived. • Comparison to literature data is discussed. • A recommended empirical line list is provided for the 8210–8670 cm−1 region. The weak high-resolution absorption spectrum of natural acetylene has been recorded by high sensitivity cavity ring down spectroscopy (CRDS) near 1.2 µm. The frequency scale of the spectra was obtained by coupling the CRDS spectrometer to a self-referenced frequency comb. The room temperature recordings, performed at a pressure of 10.0 Torr, cover the 8210–8670 cm−1 spectral interval. A list of more than 11,000 lines was constructed in the region. The smallest intensity values are on the order of 10−29 cm/molecule which is more than two orders of magnitude smaller than previous measurements by Fourier transform spectroscopy (FTS). More than 2600 lines were rovibrationally assigned using previous observations and predictions based on the effective operator approach. They include 2270, 338 and 28 absorption lines of 12C 2 H 2 , 12C13CH 2 and 12C 2 HD, respectively, belonging to a total of 52 vibrational bands, thirty-six of them being newly reported. For comparison, the HITRAN2016 database provides line parameters of only two 12C 2 H 2 bands, in the same region. Spectroscopic parameters of the upper vibrational levels were derived from standard band-by-band fits of the line positions (typical rms values of the (obs.-calc.) deviations are better than 0.002 cm–1). The vibrational transition dipole moment squared and Herman-Wallis coefficients of 39 bands were derived from a fit of the intensity values measured in this work and combined with previous FTS data for the strongest bands. A recommended list is constructed in the region using calculated line parameters for the unperturbed bands and experimental positions and intensities for the others. The recommended list including a total of 3139 transitions will help to complete acetylene spectroscopic databases in the near-infrared. [Display omitted] [ABSTRACT FROM AUTHOR]

The line positions and intensities of carbon dioxide isotopologues have been retrieved in the 4681–5337 cm −1 spectral range from Fourier transform spectra of carbon dioxide recorded in LADIR (Paris, France) with the Bruker IFS 125-HR [Jacquemart D, et al., J Quant Spectrosc Radiat Transf 2012;113:961–975]. In total 6386 line positions and intensities of 89 bands of 12 isotopologues 16 O 12 C 16 O, 16 O 13 C 16 O, 16 O 12 C 18 O, 16 O 12 C 17 O, 16 O 13 C 18 O, 16 O 13 C 17 O, 18 O 12 C 18 O, 17 O 12 C 18 O, 17 O 12 C 17 O, 18 O 13 C 18 O, 17 O 13 C 18 O, and 17 O 13 C 17 O have been retrieved. 23 bands were newly assigned. All studied bands belong to the Δ P =7 series of transitions, where P = 2 V 1 + V 2 + 3 V 3 is the polyad number ( V i are vibrational quantum numbers). The accuracy of the line position measurement is about 0.3×10 −3 cm −1 for the unblended and not very weak lines. The accuracy of the line intensities varies from 4% to 15% depending on the isotopologue, on the intensity of the line and on the extent of the line overlapping. The observed intensities were used to fit the effective dipole moment parameters for the Δ P =7 series of transitions in 16 O 12 C 18 O, 16 O 12 C 17 O, 12 C 17 O 2 , 17 O 12 C 18 O, 16 O 13 C 17 O, 13 C 17 O 2 and 17 O 13 C 18 O isotopologues of carbon dioxide. [ABSTRACT FROM AUTHOR]

Abstract: The line positions and intensities of carbon dioxide isotopologues have been retrieved in 3200–4700cm−1 region from Fourier transform spectra of carbon dioxide recorded in LADIR (Paris, France) with the Bruker IFS 125-HR [Jacquemart D et al. J Quant Spectrosc Radiat Trans 2012;113:961–75]. In total 11318 line positions and intensities of 151 bands of 12 isotopologues 16O12C16O, 16O13C16O, 16O12C18O, 16O12C17O, 16O13C18O, 16O13C17O, 18O12C18O, 17O12C18O, 18O13C18O, 17O12C17O, 17O13C18O, and 17O13C17O have been retrieved. 53 bands were newly assigned. All studied bands belong to the ΔP=5 and ΔP=6 series of transitions, where is the polyad number (V i are the vibrational quantum numbers). The accuracy of the line position measurement is about 0.3×10−3 cm−1 for the unblended and not very weak lines. The accuracy of the line intensities varies from 4% to 15% depending on the isotopologue, on the intensity of the line and on the extent of the line overlapping. The spectroscopic constants for the majority of the observed bands have been derived. The observed line positions together with those collected from the literature were used to fit the effective Hamiltonian parameters for the 16O12C17O and 17O12C17O isotopologues. In both cases the fitted models were capable of reproducing the measured line positions with accuracy compatible with the measurement uncertainties (rms are 0.0011cm−1 and 0.0009cm−1 for 16O12C17O and 17O12C17O, respectively). The observed intensities were used to fit the effective dipole moment parameters for the ΔP=5 and ΔP=6 series of transitions of 16O12C17O, 17O12C17O and 16O12C18O isotopologues of carbon dioxide. [Copyright &y& Elsevier]

Abstract: Fourier transform spectra of carbon dioxide enriched in 17O and 18O have been recorded in LADIR (Paris, France) with the Bruker IFS 125-HR between 2000 and 9000cm−1 at an unapodized resolution of 0.0056cm−1. In this contribution we present a total of 1861 line positions and intensities retrieved for 46 bands of 12CO2 isotopologues between 2000 and 7000cm−1 including the 16O12C16O, 17O12C17O, 18O12C18O, 16O12C18O, 16O12C17O, and 17O12C18O species. The objective of this first part of work was to examine the absolute concentrations of various CO2 isotopologues in the sample by comparing our measurements of the line intensities to those available in literature and in HITRAN 2008. The accuracy of the determined abundances of the various isotopologues in our sample could be estimated to be about 2–7% for all above listed isotopologues except for 17O12C17O for which the accuracy on abundance is estimated to be around 20%. The accuracy of the line positions retrieval is better than 0.1×10−3 cm−1. We estimate the relative uncertainty of the line intensities retrieval to be around 1–2% (except for very weak lines), whereas the absolute accuracy to be around 3–15% depending mainly on the accuracy of the determination of the partial pressures for the various isotopologues in our sample, but also on the line strengths and on the spectral region. The estimation of the partial pressures of the various CO2 isotopologues is crucial for retrieving absolute values of line intensities, but this is not an easy task because there are no absolute calibration standards for CO2 intensities. Among the results obtained in this work, measurements are obtained for the first time for the 10011–00001 band of 17O12C17O, 16O12C17O, 16O12C18O, and 18O12C18O species, for the 00011–00001 band of 17O12C18O, and for the 2001i–00001 (i=1, 2, and 3) bands of the 16O12C17O isotopologue. [Copyright &y& Elsevier]

Abstract: Absorption spectra of carbon dioxide, 12C16O2, have been studied in the three wavenumber ranges (8790–8860, 9340–9650 and 11,430–11,505cm−1) of the near infrared region using spectrophotometric complex of V.E. Zuev Institute of Atmospheric Optics based on an Bruker IFS 125 HR and a 30m multipass cell with the White type optical system. The spectra were recorded at spectral resolution of 0.015cm−1, path length of 613.82m and at pressure range from 209 to 400mbar. The multispectrum fittings with the Voigt profile were performed to retrieve the line positions and intensities of eight bands 5001r−00001 (r=3, 4), 2003r−00001 (r=1,2,3) 2113r−01101 (r=1,2) and 00051−00001. The uncertainty of the line position determination is estimated to be about 0.001cm−1. The absolute accuracy of the line intensity measurement is 5% for 5001r−00001 (r=3,4) bands, 3% for 2003r−00001 (r=1,2,3) bands, 10% for 00051−00001 band and 15% for 2113r−01101 (r=1,2) bands. The measured line intensities were used to fit the effective dipole moment parameters of 12C16O2. The fitted parameters reproduce the measured line intensities within their experimental uncertainties. A comparison of measured positions and intensities with those contained in HITRAN, CDSD, AMES-296, and High-T databases is presented and discussed. [Copyright &y& Elsevier]