High Resolution Wavenumber Standards for the Infrared

Guelachvili, G.; Birk, M.; Bordé, Ch. J.; Brault, J. W.; Brown, L. R.; Carli, B.; Cole, A. R. H.; Evenson, K. M.; Fayt, A.; Hausamann, D.; Johns, J. W. C.; Kauppinen, J.; Kou, Q.; Maki, A. G.; Rao, K. Narahari; Toth, R. A.; Urban, W.; Valentin, A.; Vergès, J.; Wagner, G.; Wappelhorst, M. H.; Wells, J. S.; Winnewisser, Brenda P.; Winnewisser, M.

doi:10.1515/iupac.68.0196

Cited by 3 publications

(3 citation statements)

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“…Some of the mid-infrared water studies predated the better accuracy calibration standards [89,90]. At longer wavelengths, adjustments were made to resolve inconsistencies noticed during the MARVEL analysis (see Table 4 of Part III).…”

Section: Levels and Linesmentioning

confidence: 99%

A database of water transitions from experiment and theory (IUPAC Technical Report)

Tennyson

Bernath

Brown

et al. 2014

Pure and Applied Chemistry

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Abstract:The report and results of an IUPAC Task Group (TG) formed in 2004 on "A Database of Water Transitions from Experiment and Theory" (Project No. 2004-035-1-100) O, are determined from measured transition frequencies. The transition frequencies and energy levels are validated using first-principles nuclear motion computations and the MARVEL (measured active rotational-vibrational energy levels) approach. The extensive data including lines and levels are required for analysis and synthesis of spectra, thermochemical applications, the construction of theoretical models, and the removal of spectral contamination by ubiquitous water lines. These datasets can also be used to assess where measurements are lacking for each isotopologue and to provide accurate frequencies for many yet-to-be measured transitions. The lack of high-quality frequency calibration standards in the near infrared is identified as an issue that has hindered the determination of high-accuracy energy levels at higher frequencies. The generation of spectra using the MARVEL energy levels combined with transition intensities computed using high accuracy ab initio dipole moment surfaces are discussed. A recommendation of the TG is for further work to identify a single, suitable model to represent pressure-(and temperature-) dependent line profiles more accurately than Voigt profiles.

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Section: Levels and Linesmentioning

confidence: 99%

A database of water transitions from experiment and theory (IUPAC Technical Report)

Tennyson

Bernath

Brown

et al. 2014

Pure and Applied Chemistry

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“…An example is provided by the high-resolution spectroscopic data measured by Guelachvili for H 2 16 O, and a couple of its isotopologues, and reported in 1983 in the 1066−2296 cm −1 region. 106 These data were revised about a decade later, 107 when Guelachvili et al introduced a calibration factor of 0.99999977, improving substantially the accuracy of the measured lines. Although the deviation of this factor from 1.0 appears to be small, many FTS measurements have a relative accuracy considerably better than 10 −7 , under ideal conditions this can be 10 −9 −10 −10 .…”

Section: Marvelmentioning

confidence: 99%

Small Molecules—Big Data

2016

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Quantum mechanics builds large-scale graphs (networks): the vertices are the discrete energy levels the quantum system possesses, and the edges are the (quantum-mechanically allowed) transitions. Parts of the complete quantum mechanical networks can be probed experimentally via high-resolution, energy-resolved spectroscopic techniques. The complete rovibronic line list information for a given molecule can only be obtained through sophisticated quantum-chemical computations. Experiments as well as computations yield what we call spectroscopic networks (SN). First-principles SNs of even small, three to five atomic molecules can be huge, qualifying for the big data description. Besides helping to interpret high-resolution spectra, the network-theoretical view offers several ideas for improving the accuracy and robustness of the increasingly important information systems containing line-by-line spectroscopic data. For example, the smallest number of measurements necessary to perform to obtain the complete list of energy levels is given by the minimum-weight spanning tree of the SN and network clustering studies may call attention to "weakest links" of a spectroscopic database. A present-day application of spectroscopic networks is within the MARVEL (Measured Active Rotational-Vibrational Energy Levels) approach, whereby the transitions information on a measured SN is turned into experimental energy levels via a weighted linear least-squares refinement. MARVEL has been used successfully for 15 molecules and allowed to validate most of the transitions measured and come up with energy levels with well-defined and realistic uncertainties. Accurate knowledge of the energy levels with computed transition intensities allows the realistic prediction of spectra under many different circumstances, e.g., for widely different temperatures. Detailed knowledge of the energy level structure of a molecule coming from a MARVEL analysis is important for a considerable number of modeling efforts in chemistry, physics, and engineering.

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“…During the MARVEL process it became apparent that line positions from some specific studies had been calibrated with frequency standards that were less accurate (and in some cases inconsistent) than currently available information. Some of the mid-infrared water studies predated the better accuracy calibration standards [89,90]. At longer wavelengths, adjustments were made to resolve inconsistencies noticed during the MARVEL analysis (see Table 4 of Part III).…”

Section: Levels and Linesmentioning

confidence: 99%

A database of water transitions from experiment and theory (IUPAC Technical Report)

2014

Chemistry International

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High Resolution Wavenumber Standards for the Infrared

Cited by 3 publications

References 0 publications

A database of water transitions from experiment and theory (IUPAC Technical Report)

A database of water transitions from experiment and theory (IUPAC Technical Report)

Small Molecules—Big Data

A database of water transitions from experiment and theory (IUPAC Technical Report)

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