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The global modeling of both line positions and intensities of the acetylene molecule in the 50–9900 cm −1 region has been performed using the effective operators approach. The parameters of the polyad model of effective Hamiltonian have been fitted to the line positions collected from the literature. The used polyad model of effective Hamiltonian takes into account the centrifugal distortion, rotational and vibrational ℓ -doubling terms and both anharmonic and Coriolis resonance interaction operators arising due to the approximate relations between the harmonic frequencies: ω 1 ≈ ω 3 ≈5 ω 4 ≈5 ω 5 and ω 2 ≈3 ω 4 ≈3 ω 5 . The dimensionless weighted standard deviation of the fit is 2.8. The fitted set of 237 effective Hamiltonian parameters allowed reproducing 24,991 measured line positions of 494 bands with a root mean squares deviation 0.0037 cm −1 . The eigenfunctions of the effective Hamiltonian corresponding to the fitted set of parameters were used to fit the observed line intensities collected from the literature for 15 series of transitions: Δ P = 0-13,15, where P =5 V 1 +5 V 3 +3 V 2 + V 4 + V 5 is the polyad number ( V i are the principal vibrational quantum numbers). The fitted sets of the effective dipole moment parameters reproduce the observed line intensities within their experimental uncertainties 2–20%. [ABSTRACT FROM AUTHOR]

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: Using FT spectra (unapodized resolution ~0.0056cm−1) of the nitrous oxide isotopologue , the line positions and intensities have been measured for 511 lines of 8 cold bands and one hot band lying between 5800 and 7600cm−1. A multispectrum fitting procedure has been used to retrieve line parameters from 5 experimental spectra recorded at different pressures. An absolute wavenumber calibration has been performed using acetylene line positions around 6500cm−1 and water line positions in the 7100–7300cm−1 region. The average absolute accuracy of the line parameters obtained in this work has been estimated to be ±0.0005cm−1 for the line positions, 2–5% for the line intensities depending on the transitions. For each studied band, the vibrational transition dipole moment squared value and the empirical Herman–Wallis coefficients have been determined. Moreover, the line positions measured in this work and those collected from the literature allowed the global fitting of the effective Hamiltonian parameters for this isotopologue. [Copyright &y& Elsevier]

Abstract: Using FT spectra (Bruker IFS 120, unapodized resolution≈0.01cm−1) of acetylene 12C2H2, line positions and intensities, as well as self-broadening and -shifting coefficients are measured for about 550 lines of 13 bands between 5000 and 6000cm−1. A multispectrum fitting procedure is used to retrieve line parameters from four experimental spectra recorded at different pressures. An absolute wavenumber calibration has been performed using isolated acetylene line positions around 5900cm−1. The average accuracy of the line parameters obtained in this work is estimated to be ±0.001cm−1 for line positions, 5–10% for line intensities depending on the transitions, about 5% for self-broadening coefficients, and ±0.005cm−1 atm−1 for self-shifting coefficients. For each studied band, the vibrational transition dipole moment squared and the empirical Herman–Wallis coefficients are adjusted. The measured line intensities allow to obtain the effective dipole moment parameters of the global approach for the ΔP=8 and 9 series. A polynomial description of the rotational dependence of self-broadening coefficients is performed. A weak rotational dependence of the self-shifting coefficients is observed. [Copyright &y& Elsevier]

The line positions and intensities of carbon dioxide isotopologues have been retrieved between 5900 and 6400 cm −1 region from Fourier transform spectra of 17 O- and 18 O-enriched carbon dioxide recorded in LADIR (Paris, France) with the Bruker IFS 125-HR. In total 1634 line positions and intensities of 20 bands of the 5 major CO 2 isotopologues present in our sample 16 O 12 C 17 O (39.48%), 17 O 12 C 17 O (27.73%), 16 O 12 C 16 O (15.20%), 16 O 12 C 18 O (7.32%) and 17 O 12 C 18 O (8.25%) are retrieved. All studied bands belong to the Δ P =8 (only for asymmetric species) and 9 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 determination is about 0.3×10 −3 cm −1 for the unblended and not very weak lines and the accuracy for the line intensities varies from 4% to 30% depending on the intensity of the line and on the extent of the line overlapping. For the 16 O 12 C 17 O, 17 O 12 C 17 O, 16 O 12 C 18 O and 17 O 12 C 18 O isotopologues the systematic comparisons have been performed with the recent CRDS measurements. [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]

The absorption spectra of carbon dioxide have been recorded in two wavenumber ranges 9250–9500 cm −1 and 10,700–10,860 cm −1 of the near infrared region using a Bruker IFS 125 HR Fourier transform spectrometer and a 30 m multipass cell with the White type optical system. The spectra were recorded at spectral resolution of 0.03 cm −1 , room temperature, path length of 726.7 m and at four pressures ranging from 187 to 674 mbar. The achieved sensitivity (noise equivalent absorption) at the level of k ν =7.2×10 −10 cm −1 allowed detection of numerous new transitions with intensity values down to 5×10 −29 cm/molecule. The respective measurement time is about 20 h. The multispectrum fittings with the Voigt profile were performed to retrieve the line positions and intensities of 12 observed bands. Three hot bands of 12 C 16 O 2 in the 9250–9500 cm −1 region were detected for the first time. The line intensities of 30032−00001 and 30033−00001 bands of 12 C 16 O 2 and of 20032−00001 band of 16 O 12 C 18 O were measured for the first time. The uncertainty of the line position determination is estimated to be about 0.001 cm −1 for the unblended lines with high value of signal-to-noise ratio. The uncertainty of the line intensity determination varies from 5% to 40% depending on the line strength and on extent of line overlapping. The measured line intensities of 30032−00001 and 30033−00001 bands together with those published for the 00051−00001 band were used to fit the effective dipole moment parameters of 12 C 16 O 2 for the Δ P =15 series of transitions, where P =2 V 1 + V 2 +3 V 3 is a polyad number ( V i ( i =1,2,3) are vibrational quantum numbers). The fitted parameters reproduce the measured line intensities within experimental uncertainties. Comparison of the measured line positions and intensities to those contained in HITRAN, GEISA, CDSD and AMES line lists is given. [ABSTRACT FROM AUTHOR]

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]

Abstract: Spectroscopic data are noticeably enriched in six spectral regions of the main isotopologue 12C2H2 of the acetylene molecule, namely, in the regions around 3, 2.2, 1.9, 1.7, 1.5, and 1.4μm. Among these regions, only those at 3 and 1.5μm were already presented partly in the databases. The results of line intensity measurements, performed for the first time in the 1.4μm region, are given. Data available in the literature, or obtained in the present work, are compiled to set up line lists usable for applications in the quoted spectral regions. On the whole, 5748 new lines pertaining to 65 bands can be added to the databases. [Copyright &y& Elsevier]

Abstract: Using FT spectra (Bruker IFS 120, unapodized FWHM resolution ≈ 0.001cm−1) of acetylene 12C2H2, absolute positions and intensities have been measured for about 250 lines between 2600 and 2800cm−1 in the and cold bands, and in the and hot bands. These measurements improve the accuracy of wavenumbers previously available and lead to individual line intensities for the first time in this spectral region. A multispectrum fitting procedure has been used to retrieve line parameters from five experimental spectra recorded at different pressures. The frequencies of the ν 3 band of 12C16O2 allowed to perform an absolute wavenumber calibration. The accuracy of the amount of 12C2H2 in the sample has been checked using the cold band around 2100cm−1, and has been estimated to be around ±2%. The average absolute accuracy of the line parameters obtained in this work has then been estimated to be ±0.0002cm−1 for line positions, and ±5% for line intensities. For each studied band, the vibrational transition dipole moment squared value has been determined, as also empirical Herman–Wallis coefficients. A complete line list containing positions and intensities for the five strongest bands around 3.8μm has been set up for atmospheric applications. [Copyright &y& Elsevier]