Activation of methane by Rh(0): Evidence for direct insertion of rhodium into the C–H bond at cryogenic temperatures

The ground state rhodium atoms react with methane in solid argon to form the insertion product HRhCH3 spontaneously upon annealing. The HRhCH3 molecule is characterized by Rh–H stretching and CH3 deformation vibrations at 2035.1 and 1180.3 cm−1. The observation of direct insertion is in good agreement with previous theoretical predictions that the neutral rhodium atom has a low barrier for activating the C–H bond of methane.