Line list of HD 18 O rotation-vibration transitions for atmospheric applications Semen MIKHAILENKO, Olga NAUMENKO, and Sergei TASHKUN Laboratory of Theoretical Spectroscopy, V.E. Zuev Institute of Atmospheric Optics, Tomsk, RUSSIA An-Wen LIU and Shui-Ming HU Hefei National Laboratory for Physical Sciences at Microscale, University of Science and Technology of China, Hefei, , CHINA The HD 18 O molecule was detected recently in the upper Earth’s atmosphere [1]. We present and discuss here a line list of HD 18 O aimed at atmospheric applications. Experimental transitions in the cm -1 region originating from different experimental sources [2-12] have been validated based on the theoretical computations by Partridge and Schwenke (PS) [13, 14] and the set of 3033 precise experimental energy levels has been obtained using the fundamental Rydberg-Ritz principle [15]. General information about presented line list and comparison with HITRAN data are presented in Tables 1 and 2. Our detailed and accurate line list of the HD 18 O rotation-vibration transitions has been constructed based on the experimental energy levels and PS intensities. Accuracy of line positions included into the line list is illustrated by Figs. 1 and 2, The ( OBS - CALC ) differences on Fig. 1 are given for a whole region considered. Differences for most accurate transitions with the declared experimental uncertainties not exceeding cm -1 are shown on Fig. 2. Quality of the PS intensities involved in the line list is confirmed by the comparisons with available experimental data which are shown on Figs. 3 and 4. HD 18 O line list for atmospheric applications has been constructed by scaling the PS intensities to the natural abundance ( 6.23x10 -7 according to [16]) and applying the intensity cutoff of cm/molecule at 296 K. A comparison of our line list and HITRAN data is given in Table 1. All variationally predicted HD 18 O lines important for evaluation of the solar radiation absorption by the Earth atmosphere are shown in Fig. 5 (upper panel); middle panel corresponds to total absorption due to HD 18 O transitions included into our line list; low panel represents residual absorption. The calculated absorption spectra of the atmospheric air with (upper panel) and without (middle panel) contribution from water vapor, and HD 18 O (lower panel) in cm -1 spectral range are given in Fig. 6. Contribution of the HD 18 O absorption lines is clearly seen in the region of rotational bands and near 1500 and 3900 cm -1. Fig. 5. Atmospheric absorption with (upper panel) and without (middle panel) water vapor. Lower panel – absorption of HD 18 O References 1. Z. Zelinger et al., Molecular Physics, 104 (2006) G. Steenbeckeliers,Private communication (July 1971). 3. J.W. Fleming, M.J. Gibson, J. Mol. Spectrosc. 62 (1976) J.W.C. Johns, JOSA, B2 (1985) R.A. Toth, J. Mol. Spectrosc. 162 (1993) R.A. Toth, J. Mol. Spectrosc. 198 (1999) R.A. Toth, J. Mol. Structure, 742 (2005) A.-W. Liu et al., J. Mol. Spectrosc. 237 (2006) F. Mazzotti et al., J. Mol. Spectrosc. 243 (2007) S.N. Mikhailenko et al., JQSRT, 110 (2009) A.-W. Liu et al., JQSRT, 110 (2009) O.V. Naumenko et al., JQSRT, 111 (2010) H. Partridge, D.W. Schwenke, J. Chem. Phys. 106 (1997) D.W. Schwenke, H. Partridge, J. Chem. Phys. 113 (2000) S.N. Mikhailenko et al., Oral FA06 on 65 th OSU Symposium, Columbus, OH, USA, June 21-25, L.S. Rothman et al., JQSRT, 110 (2009) Fig. 6. PS calculated (upper panel), predicted from experimental energies (middle panel) and their difference for the line positions of HD 18 O Table 1. General comparison of our and HITRAN line lists Our line listHITRAN Spectral Region (cm -1 )8 – – 3825 Number of Transitions Cut-off (cm/molecule)1x x *), 2x Number of Bands184 J max, K a max 20, 1113, 9 *) Only for pure rotational band Band Number of Transitions Region / cm -1 (000) – (000) 9868 – 668 (010) – (010) – 329 (010) – (000) – 1834 (020) – (010) – 1496 (100) – (000) – 2992 (020) – (000) – 3160 (001) – (000) – 3984 (110) – (000) – 4344 (030) – (000) – 4311 (011) – (000) – 5348 (200) – (000) – 5463 (040) – (000) – 5333 (101) – (000) – 6575 (021) – (000) – 6538 (210) – (000) – 6786 (002) – (000) – 7434 (012) – (000) – 8702 (003) – (000) – Table 2. Overview of our line list Fig. 1. Deviations of observed ( OBS ) and calculated ( CALC ) line positions for the whole spectral region Fig. 2. Deviations of observed ( OBS ) and calculated ( CALC ) wavenumbers for precise line positions (with uncertainties not exceeding cm -1 ) Fig. 3. I OBS / I PS intensity ratio for the line intensities of the 2 band [5]. Fig. 4. I OBS / I PS intensity ratio for the line intensities in the cm -1 region. Calculation conditions for Fig. 5 Pressure – 1 atm Path – 1200 m Apparatus resolution – 0.01 cm -1 Apparatus function – SINC**2 Temperature – 296 K Gas mixture: Water – 1.863% Carbon dioxide – % Ozone – 3  % Nitrous oxide – 3.2  % Carbon monoxide – 1.5  % Methane – 1.68  % Oxygen – % Nitrogen – %