DFT studies for dehydrogenation of methane by gas-phase Ru+

► We studied the gas-phase activation of methane by Ru+. ► A spin crossing occurs from 4RuH(CH3)+ to 2RuH2(CH2)+. ► No barrier in excess of the endothermicity of the H2 elimination reaction. ► The reactions to produce RuH+ and RuCH3+ are situated at more than 50 kcal/mol.