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14 AND
16 BANDS IN THE 10 µM FOR TRANS-ACROLEIN.
XINGJIE JIANG, LI-HONG XU, Centre for Laser, Atomic and Molecular Sciences (CLAMS), Dept. of Physical Sciences, Univ. of New Brunswick, Canada E2L 4L5; A. R. W. MCKELLAR, Steacie Institute for Molecular Sciences, National Research Council of Canada, Ottawa, Canada.
\hspace1cm Acrolein (CH2CHCHO) is one of the four (in addition to methanol CH3OH, acetaldehyde CH3CHO, and 1,3-butadiene CH2CHCHCH2) 2004 target molecules from main- and side-stream (MS and SS) cigarette smoke^[1]. The present work is aimed at extending the database of high resolution laboratory spectroscopic information on the molecule in the 10 µm region.
\hspace1cm We have obtained 10 µm high resolution spectra from NRC both at room and cooled temperatures at 0.002 cm-1 resolution. The spectra cover several vibrational bands including the two dominant ones, the
16 CH2 out-of-plane rocking and
14 CH2 twisting. Analyses of the
16 and
14 bands are now at advanced stages. More specifically, about 1085 lines have been assigned to the
16 band for transitions to upper state Ka' = 0, 1, 2, 3, 4, 5, 6, 7, 8, 9 and 10, and about 800 lines have been assigned to the
14 band for transitions to upper state Ka' = 1, 2, 3, 4, 5, 6, 7 and 8. We have applied an isolated band model to each band using Maki's asymmetric rotor Hamiltonian in which some assigned transitions were removed from our fits. In our analysis, we have encountered challenges due to high line density as well as perturbations. For the latter, J-reduced upper state term values have been obtained and plotted as a function of J, indicating possible interactions among the two states.
\hspace1cm For intensity information, we have carried out ab ~initio dipole derivative calculations using the procedure explained in Ref. [2] for 1,3-butadiene. A line list with position and intensity has been compiled using the ab ~initio dipole derivatives and the rotational constants obtained from the present work.
\hrule \hspace1cm em[1] Private communication from Aerodyne Research, Inc., and Phillip Morris Research Center. em[2] Z.D. Sun, Li-Hong Xu, R.M. Lees, X.J. Jiang, S. Perry, N.C. Craig, J. Mol. Struct. 742 (2005) 69-76.