The main spectroscopic technique for studying radicals in solids and liquids, ESR, cannot usually be used to study radicals of more than 3-5 atoms in the gas phase due to strong coupling between the spin, rotational, and orbital angular momenta. Muon spin rotation/relaxation/resonance (MuSR) does not suffer from this problem, potentially making it superior for gas phase measurements. We are attemping to demonstrate RF MuSR as a new tool for measuring organic radicals in the gas phase, opening up the possibility of final state spectroscopy on such systems. This proposal aims to measure the cyclohexadienyl radical formed in benzene vapour.