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We use optical frequency comb Fourier transform spectroscopy to measurehigh-resolution spectra of iodomethane, CH$_3$I in the C-H stretch region from2800 to 3160 cm$^{-1}$. The fast-scanning Fourier transform spectrometer withauto-balanced detection is based on a difference frequency generation comb withrepetition rate, f$_{rep}$, of 125 MHz. A series of spectra with sample pointspacing equal to f$_{rep}$ are measured at different f$_{rep}$ settings andinterleaved to yield sampling point spacing of 11 MHz. Iodomethane isintroduced into a 76 m long multipass absorption cell by its vapor pressure atroom temperature. The measured spectrum contains three main ro-vibrationalfeatures: the parallel vibrational overtone and combination bands centeredaround 2850 cm$^{-1}$, the symmetric stretch ${\nu}_1$ band centered at 2971cm$^{-1}$, and the asymmetric stretch ${\nu}_4$ band centered at 3060cm$^{-1}$. The spectra of the ${\nu}_4$ band and the nearby${\nu}_3$+${\nu}_4$-${\nu}_3$ hot band are simulated using PGOPHER and a newassignment of these bands is presented. The resolved ro-vibrational structuresare used in a least square fit together with the microwave data to provide theupper state parameters. We assign 2603 transitions to the ${\nu}_4$ band withstandard deviation (observed - calculated) of 0.00034 cm$^{-1}$, and 831transitions to the ${\nu}_3$+${\nu}_4$-${\nu}_3$ hot band with standarddeviation of 0.00084 cm$^{-1}$. The hyperfine splittings due to the ${^{127}}$Inuclear quadrupole moment are observed for transitions with J$\leq$2xK.Finally, intensities of 157 isolated transitions in the ${\nu}_4$ band arereported for the first time using the Voigt line shape as a model inmultispectral fitting.

Line Positions and Intensities of the {\nu}$_4$ Band of Methyl Iodide Using Mid-Infrared Optical Frequency Comb Fourier Transform Spectroscopy