On the "expanded local mode" approach applied to the methane molecule
Résumé
Methane (CH4 ) is one of the main prototypical hydrocarbons and is of great importance in a variety of applications ranging from our understanding of the chemical bonding, structure and quantum dynamics, reaction kinetics to geology, astrophysics, atmospheric and environmental science. On that reason, during more than five last decades both the vibrational and ro-vibrational spectra of methane were a subject of numerous studies (see, for example, M.Hippler and M.Quack, J. Chem. Phys. 116 (2002) 6045. and H.M.Niederer, S.Albert, S.Bauerecker, V.Boudon, J.P.Champion and M.Quack, Chimia 62 (2008) 273 where extensive references to spectroscopic and theoretical works can be found, the complete, very long list being not reproduce here).