The CH₃ asymmetric stretchings of p‐halogenotoluenes

The vibrational spectra of p ‐halogenotoluenes and o ‐fluorotoluene in the region of the CH 3 asymmetric stretchings are reported. The observed bands at 2997, 2987, 2975 and 2945 cm −1 at 77 K in p ‐fluorotoluene are asslgned to the B 2 , A 1 , A 2 and B 1 modes, respectively, on the basis of the C 20 symmetry. Two Raman bands at 2971 and 2945 cm −1 at 77 K in p ‐chlorotoluene are assigned to the B 2 and B 1 modes, respectively, where the former in the liquid state is a polarized band and is assigned also to the A 1 mode. This is also true for p ‐bromotoluene.