Contribution to the study of the 2 ν5 ( A1) rovibrational band of CH 3Br near 2860 cm -1

This band was studied on a Fourier Transform spectrum (resolving power of the apparatus: 0.005 cm ^-1). For each isotopic species CH ₃⁷⁹Br and CH ₃⁸¹Br, about 800 lines were assigned. The band is well explained by a x- y type Coriolis interaction with ν₂ + ν₅. Several local resonances occur for low K values as well as a doubling of the K = 3 levels. Their study provides interesting information on neighboring bands, especially 3 ν₆( E), ν₂ + ν₃ + ν₆, and 2 ν₅( E).