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The IUPAC water vapour database

The IUPAC water vapour database. Jonathan Tennyson HITRAN meeting Department of Physics and Astronomy Harvard University College London June 2008. A Database of Water Transitions from Experiment and Theory.

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The IUPAC water vapour database

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  1. The IUPAC water vapour database Jonathan Tennyson HITRAN meeting Department of Physics and Astronomy Harvard University College London June 2008

  2. A Database of Water Transitionsfrom Experiment and Theory Members: Jonathan Tennyson (chair), P.F. Bernath, A. Campargue, M.R. Carleer, A.G. Császár, R.R. Gamache, J. Hodges, (A. Jenouvrier), O. Naumenko, O.L. Polyansky, L.S. Rothman, R.A. Toth, A.C. Vandaele, N.F. Zobov L Brown, L Daumont Objective: Develop a compilation of experimental and theoretical line positions, energy levels, intensities, and line-shape parameters for water vapour and all of its major isotopologues Establish a database structure that retains and enables access to all critically evaluated data

  3. IUPAC Task group Database (W@DIS) in parts: • Energy levels and frequencies (MARVEL): progress update • Line intensities is best way forward ab initio? • Pressure dependence Gamache et al • Archive: experimental data and calculated linelists. Alex Fazliev • Will use: • multiple data sources for each region • back filled by theory

  4. “Water continuum”: Anomalous Features • 6.4*1019 molecules cm-3 • T = 95 C • All fitting parameters (except water database)identical for both cases. ‘Continuum Feature’ (HITRAN) No feature (UCL) A.J.L. Shillings and R.L. Jones, University of Cambridge

  5. Iodine Measurements • Iodine released by certain seaweeds when under stress (low tide). • Emitted I2 leads to significant aerosol production and has an impact on ozone chemistry. • Need accurate I2 measurements to better understand detailed mechanisms involved. • Retrieved I2 and NO2 concentrations depend on the water database employed. • Disagreement for I2 up to ± 20 ppt, (which is chemically significant), NO2 disagreement up to ±0.65 ppb (UCL 08 gives better agreement with independent chemiluminescence NO2 measurements). A.J.L. Shillings, S.M. Ball and R.L. Jones, University of Cambridge Measurements performed during RHaMBLe campaign, Roscoff, France, 2006.

  6. MARVEL: inverse, experimentalrovibrational energy levelsMeasured Active Rotational-Vibrational Energy Levels Based on: 1. X-matrix protocol of Flaudet al (1976) applied to allspectra 2. Relatively robust error method of Watson T. Furtenbacher, A. G. Császár, J. Tennyson, J. Mol. Spectrosc. 245, 115 (2007) T. Furtenbacher, A. G. Császár, J. Quant. Spectr. Rad. Transfer109, 1234 (2008)

  7. Observed transition wavenumbers ij with assignments and uncertainties The ij can be determined by term values Ei, Ej, .... Assignment i,j ij .....+1 ...... -1 ........ Ei ...... .... = × Ej ....  = X× E Solve for E (least-squares with experimental uncertainties of the ij) obtain experimentally derived term values Ei, Ej, ....

  8. Spectroscopic networks of water Water (except for HDO) has twomain SNs: (Ka + Kc + n3) is even (Ka + Kc + n3) is odd (para) (ortho) „magic number”

  9. Collect, validate, and compile all available measuredtransitions, including their systematic andunique assignments and uncertainties, into a single database. • Based on the given database of assigned transitions, determine those energy levels of the given species which belong to a particular spectroscopic network (SN). • (3) Cleansing of the database (misassignments, mislabelings). • (4) Within a given SN, set up a vector containing all the experimentally measured transitions selected, another one comprising the requested measured energy levels, and a design matrix which describes the relation between the transitions and the energy levels. • (5) Solve the resulting set of linear equations corresponding to the chosen set of vectors and the inversion matrix many times (robust reweighting). During solution of the set of linear equations uncertainties in the measured transitions can be incorporated which result in uncertainties of the energy levels determined. MARVEL steps

  10. Input database Freq/cm-1 unc./10-6 cm-1 assignment unique label other info 0.30077226 0.7659 000 7 4 3 000 7 4 4 83Johns.1 0.31558743 4.5621 00010 5 5 00010 5 6 83Johns.2 0.31723578 2.2311 000 3 2 1 000 4 1 4 83Johns.3 0.34827138 0.1998 000 2 2 0 000 2 2 1 83Johns.4 0.75701556 3.0969 000 7 1 7 000 6 2 4 83Johns.5 0.768572325 0.7326 000 5 3 2 000 5 3 3 83Johns.6 0.80647272 13.9194 000 11 5 6 00011 5 7 83Johns.7 0.872355105 0.999 000 8 4 4 000 8 4 5 83Johns.8 1.261732005 1.5318 000 4 3 1 000 5 2 4 83Johns.9 1.701219744 0.666 000 3 2 1 000 3 2 2 83Johns.10 2.161459377 1.3653 000 9 4 5 000 9 4 6 83Johns.11 2.217844602 1.0656 000 6 3 3 000 6 3 4 83Johns.12 … Java-based test facility: http://theop11.chem.elte.hu/marvel/MARVEL_JAVACODE.html

  11. [UC = under construction ] Marvel web page: http://chaos.chem.elte.hu/marvel/

  12. Observed Transitions of H217O Observed Transitions of H217O

  13. H217O vibrational energy levels

  14. MARVELlous water • Characteristics of MARVEL energy levels: • highly accurate • highly incomplete as we move up on the energy ladder

  15. Pure rotational energy levels for waterT. Furtenbacher, A. G. Császár, J. Quant. Spectr. Rad. Transfer 109, 1234 (2008)

  16. Energies/frequencies • Have well developed protocol • H217O, H218O and HD16O (nearly) complete • H216O underway: all available data input, much missing • Labeling remains an issue

  17. Intensities: • Required to better than 1% for remote sensing • Very few laboratory determinations this accurate • Problems with consistency between measurements • Issues with dynamic range of any measurements • New ab initio CVR dipole accurate to about 3% • (hope to do better soon)

  18. Intensities of pure rotational transitions Calculations using CVR dipole surface of Lodi et al JCP, 128, 0440204 (2008) Lodi & Tennyson, JQSRT, 109, 1219 (2008).

  19. Lodi & Tennyson, JQSRT, 109, 1219 (2008).

  20. Lodi & Tennyson, JQSRT, 109, 1219 (2008).

  21. Lodi & Tennyson, JQSRT, 109, 1219 (2008).

  22. Lodi & Tennyson, JQSRT, 109, 1219 (2008).

  23. Lodi & Tennyson, JQSRT, 109, 1219 (2008).

  24. Bending fundamental: 1250 – 1750 cm-1 CVR calc = Lodi & Tennyson, unpublished. DLR = Coudert, Wagner et al (JMS in press)

  25. Intensities: • Analysis of allowed and forbidden rotational transitions using: • (Lodi & Tennyson, JQSRT, 109, 1219 (2008). ). • 555 allowed, 846 forbidden lines > 10(-28) molecule/cm at 296 K • 50 of which not in HITRAN or JPL • Good general agreement with HITRAN for these • Significant systematic errors identified in JPL database • Subsequent analysis of bending fundamental region suggests problem with strong lines in HITRAN • Use purely ab initio calculated intensities to solve these problems? • (Resonances?!) • “UCL linelists” • Multiple sources for single region • Back filled for missing transitions with theory • Will be IUPAC convention, HITRAN too?

  26. A Database of Water Transitions from Experiment and Theory Members: Jonathan Tennyson (chair), P.F. Bernath, A. Campargue, M.R. Carleer, A.G. Császár, R.R. Gamache, J. Hodges, A. Jenouvrier, O. Naumenko, O.L. Polyansky, L.S. Rothman, R.A. Toth, A.C. Vandaele, N.F. Zobov, L. Brown Also: L Daumont, AZ Fazliev, T Furtenbacher, IF Gourdon, SN Mikhailenko, SV Shirin, BA Voronin, S Voronina, A Al Derzi UCL intensity work: L Lodi, M Barber, RN Tolchenov

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