The analysis of the torsional structures of the CH3(D3) asymmetric stretching vibrations of gaseous toluene

The torsional structures of the asymmetric stretchings of the methyl group of toluene are analyzed on the basis of the C2v symmetry. The torsional structures observed in the IR spectrum of gaseous toluene-h3 are explained by use of the twofold and sixfold potentials in the first excited state of the CH3 asymmetric stretchings. The fundamentals analyzed are 2996.3 cm−1 for the B2 mode and 2981.8 cm−1 for the B1 mode. The Raman bands observed here at 2989 and 3012 cm−1 are assigned to the fundamentals of the A1 and A2 modes, respectively. The torsional structures of the CD3 asymmetric stretchings are explained satisfactorily by use of the potential constants obtained in the CH3 system.