Submillimeter-wave spectra of 12CH3F in the v2 = 1 and v5 = 1 vibrational states

Abstract Transition frequencies of the pure rotational transitions in the v 2 = 1 and v 5 = 1 vibrational states of 12 CH 3 F between 180 and 610 GHz have been measured using the submillimeter-wave spectrometer with acoustic detection RAD3. Twenty-two spectroscopic parameters describing the vibration-rotation interactions within and between the v 2 = 1 and v 5 = 1 states have been fitted using a reduced effective Hamiltonian for interacting vibrational states proposed by Lobodenko et al. [J. Mol. Spectrosc. 126 , 159–170 (1987)].