Bond Dissociation Energies, Proton, Hydride, Electron Affinities, and Ionization Potentials of C1 Hydrocarbon Ions

Carbon and hydrocarbons are fundamental building blocks of life. Here, we present a comprehensive computational study on the stability and reactivity of CH_x^±n (X = 0, 1, 2, 3, 4) species across charge states n ranging from −4 to +4 and multiplicities from singlet to quintet. We benchmark suitable methods and select CCSD(T)/aug-cc-pVQZ for computing the bond dissociation energies (BDEs), proton affinities (PAs), hydride affinities (HAs), electron affinities (EAs), and ionization potentials (IPs). We discuss observed trends in charge-dependent stability and reactivity, with implications for a fundamental understanding of carbon–hydrogen species. We believe that these data will be useful for further investigations of highly reactive hydrocarbons in unusual electronic states.