The Raman Spectrum of Ethane

The rotational and rotation-vibrational Raman spectra of gaseous ethane at 1–3 atm. pressure have been photographed with a spectral resolution of approximately 1 cm. −1 . Analyses of the rotational structures of the ν 1 and ν 2 totally symmetric bands were carried out; only the Q branch of the ν 2 band was observed. The structures of the degenerate ν 10 and ν 11 bands were analyzed; however, no trace of ν 12 was found. The structure of the ν 10 band shows beyond doubt that the point group of the molecule is D 3d . From the ν 11 +ν 4 infrared band, and the ν 11 Raman band, the value, 278.4 cm. −1 , is deduced for the torsional frequency ν 4 .