Analysis of the high resolution spectrum of the fundamental bandsv2 andv5 of12CH3F and their interactions

Thev ₂(A₁) andv ⁵(E) fundamental vibration-rotation bands of¹²CH₃F have been recorded under high resolution (0.015 to 0.020 cm^–1) in the spectral range of 1460 cm^–1. About 1100 transitions have been assigned. The Coriolis interaction between v₂=1 and v₅=1, and the l(2,-1) interaction in v₅=1 have been rigorously treated. Sixteen molecular constants have been determined from a least squares analysis. They reproduce the observed data with an overall standard deviation of 0.0037 cm^–1.