The vibrational levels of methane obtained from analyses of high-resolution spectra

Vincent Boudon (1) , Michaël Rey (1) , Michel Loete (1)

1 LPUB - Laboratoire de Physique de l'Université de Bourgogne

Methane and its tetrahedral isotopologues are spherical-top molecules whose high-resolution rovibrational spectra can only be analyzed in detail, thanks to sophisticated symmetry-adapted tensorial models. However, the effective Hamiltonian parameters of such models do not give direct access to the positions of the vibrational sublevels. In this paper, we present a calculation of the vibrational level positions for 12CH4, 13CH4, 12CD4 and 13CD4 performed using the effective Hamiltonian parameters obtained through recent analyses. We also include the results of a re-analysis of the octad system of 12CH4 performed with a higher order of the development which slightly improves the previous work on this polyad.

Mots clés: methane; vibrational levels and sublevels; polyads; potential surface; tensorial formalism

Domaines: Physique Atmosphérique et Océanique [physics.ao-ph]

Vincent Boudon, Michaël Rey, Michel Loete. The vibrational levels of methane obtained from analyses of high-resolution spectra. Journal of Quantitative Spectroscopy and Radiative Transfer, 2006, 98, pp.394-404. ⟨10.1016/j.jqsrt.2005.06.003⟩. ⟨hal-00437080⟩