ISBN 9783843904599

978-3-8439-0459-9, Reihe Physikalische Chemie

Hans-Martin Niederer
The Infrared Spectrum of Methane

534 Seiten, Dissertation Eidgenössische Technische Hochschule (ETH) Zürich (2011), Hardcover, B5

Zusammenfassung / Abstract

New techniques of high resolution spectroscopy in conjunction with enclosive flow cooling are presented and used to obtain new data for methane covering almost the whole infrared. While some new results on 12CH4 are presented, the emphasis of the present work is on the analysis of the spectra of 13CH4. The vibrational band centers of methane are identified and the rovibrational structure of 13CH4 in its pentad and its octad region are analyzed in terms of effective Hamiltonian parameters. The group theoretical approach elaborated in the Dijon group is discussed in detail and compared to other effective Hamiltonian theories and labeling schemes of rotational energy levels for methane-like spherical-top molecules. The results on the 13CH4 infrared spectra have the potential for wider use in atmospheric chemistry and physics. It should be possible to investigate contributions of 13CH4 to the infrared absorption in the atmospheres of the Earth and of the other planets including some of their moons.