![]() |
ИСТИНА |
Войти в систему Регистрация |
ИСТИНА ЦЭМИ РАН |
||
In this study we have re-analyzed high-resolution spectra of pure CO and CO broadened by hydrogen recorded in the spectral range of the first overtone band [1]. Self- and H2-Lorentzian pressure-broadened half-width, pressure-induced shift parameters, line mixing coefficients as well as line centers and intensities were obtained for 48 (P(24) to R(23)) ro-vibrational transitions belonging to the first overtone (20) band of 12C16O at the ambient temperature (~298 K). The line coupling effect has been observed and investigated as an asymmetry in the analyzed line profiles. Two semi-empirical methods (Energy Corrected Sudden Approximation, Exponential Power Gap Law) were used to estimate the self-broadening and self-line mixing parameters. The spectra were fitted simultaneously within the range 4146 to 4332 cm-1 employing four line shape functions: the Voigt, Speed Dependent Voigt, Rautian and Speed Dependent Rautian Profiles. Furthermore, a classical approach [2] was applied to calculate the half-widths of CO absorption lines in CO-H2 and CO-CO collisions. The calculations utilize simple vibrationally independent intermolecular interaction potential (Tipping-Herman + electrostatic)[3,4]. Both molecules were treated as rigid rotors. The dependences of CO half-widths on rotational quantum number J ≤ 24 are computed at room temperature and compared with measured data. Acknowledgements The research carried out at the University of Lethbridge is funded by the Natural Sciences and Engineering Research Council of Canada through the Discovery and CREATE grant programs. The part of the research carried out at the College of William and Mary, Connecticut College and NASA Langley Research Center have been funded by cooperative agreements and contracts with the National Aeronautics and Space Administration. Dr. D. Chris Benner at the College of William and Mary is thanked for allowing us to use his multispectrum fitting software in analyzing the data. References [1] V. Malathy Devi et al., J. Mol. Spectrosc. 228 580 (2004). [2] R. G. Gordon, J. Chem. Phys. 44 3083 (1966). [3] J.-P. Bouanich and A. Predoi-Cross, J. Molec. Structure 742 183 (2005). [4] A. Predoi-Cross, J.-P. Bouanich, D. Chris Benner, A. D. May, and J. R. Drummond, J. Chem. Phys. 113 158 (2000).