Study of the R-Branch of the 3ν3 Band of 13CH4 in the 1-μm Region

The absorption spectrum of 13 CH 4 is studied in the range from 9000 to 9200 cm −1 at temperatures from 208 to 296 K using a Bruker IFS 125M Fourier spectrometer. Lines of the R -branch of the 3ν 3 13 CH 4 band are identified up to the rotational quantum number J = 11. The list of the lines identified includes nine previously unknown lines with high rotational quantum numbers. The symmetry type ( А 1 , А 2 , F 1 , F 2 , E ) is determined for 32 levels of the (0030) state of the 13 CH 4 molecule up to J = 10 for the first time.