Searching for the Rotational Spectrum of CH2OH

Hydroxymethyl radical (CH₂OH) is a radical fragment of methanol, and an important molecule in understanding astrochemistry. Its precursor is abundant, its isomer has already been detected towards B1-b, and it is a key intermediate in the production of more complex hydrocarbons, but its rotational spectrum is not yet known. Identification of this fragment and its isomer CH₃O in spectral data could improve our understanding of the development of chemical complexity in space, and could also be used to constrain models of desorption and branching ratios of methanol photodissociation. We sought to measure the rotational spectrum of CH₂OH to open the door for its observation in space. Spectrum predictions were made based on infrared experiments by Roberts et al., and a millimeter-wave absorption cell, operating in the 70-500 GHz range was used to search for the rotational spectrum of CH₂OH. A number of candidate lines were found, but none could be clearly identified as belonging to CH₂OH. Previously unmeasured lines of CH₃O were also determined. Future work will involve increasing the production efficiency of CH₂OH and searching for its b-type spectrum.