Line list for the ν3, ν3＋ν6–ν6 and 2ν3–ν3 bands of methyl fluoride at 9.5 μm

Abstract

Six Fourier transform spectra recorded at room temperature and for pressures ranging from 0.1 to 4 mbar were analyzed in the spectral region of the ${\nu }_3$ band of ${\mathrm{CH}}_{3}F$ around $9.5\mu m$. A multispectrum fitting procedure was used to measure the line positions and intensities for three bands (${\nu }_3$, ${\nu }_3$＋${\nu }_6$–${\nu }_6$, $2{\nu }_3$–${\nu }_3$) of ${}^{\mathrm{12}}{\mathrm{CH}}_{3}F$ and one band (${\nu }_3$) of ${}^{\mathrm{13}}{\mathrm{CH}}_{3}F$ using the Voigt profile. The measured line intensities were then modeled using the vibrational transition dipole moment squared and a weak Herman–Wallis coefficient. A theoretical calculation of line positions based on ab initio and effective Hamiltonian models was performed and then compared to present measurements and calculations from the literature. The current work finally present a complete list (in HITRAN format) of the line parameters for four bands of ${\mathrm{CH}}_{3}F$ (8907 transitions) in the $9.5\mu m$ spectral region.