Infrared combination bands of CH4 in crystal fields
Abstract
Overtone and combination bands were observed between 1000 and 5000 cm‑1 for CH4 molecules in several crystal fields: solid phases I and II, and diluted alloys with Kr. In the anisotropic field of phase II, a full (rotation/libration)-vibration spectrum was observed in the combination bands 2v4,v2+v4, andv3+v4. Here, all lines could be assigned to transitions of either D2d or Oh molecules. The structure ofv3‑v4,v2+2v4,v1+v4,v2+v3 and 3v4 bands could not be resolved. In phase I, all spectra show the characteristic features of rotational diffusion, while in a Kr matrix a rotovibrational structure could again be observed in the overtone and combination bands.
- Publication:
-
International Journal of Infrared and Millimeter Waves
- Pub Date:
- August 1987
- DOI:
- 10.1007/BF01010730
- Bibcode:
- 1987IJIMW...8..923B
- Keywords:
-
- Crystal Lattices;
- Infrared Spectra;
- Methane;
- Molecular Rotation;
- Solid Phases;
- Vibrational Spectra;
- Cryogenic Equipment;
- Frequency Shift;
- Krypton;
- Libration;
- Atomic and Molecular Physics;
- Characteristic Feature;
- Crystal Field;
- Rotational Diffusion;
- Anisotropic Field;
- Combination Band