Does Charge Matter? Direct vacuum UV measurement of ionization energies reveals that C–H insertion by Pt to form H-Pt-CH3 is highly exoergic, while production of PtCH2+H2 is slightly endoergic. Experiments and spin-orbit DFT calculations reveal surprisingly similar energetics for dehydrogenation of methane by neutral and cationic platinum. Red lines in the picture indicate experimentally determined energies.