Proton affinity of water. A scale of gas-phase basicities including ethylene and water from ion cyclotron resonance proton transfer equilibria measurements

Ion cyclotron resonance proton transfer equilibrium measurements have been used to establish a relative scale of gas-phase basicities in the proton affinity region immediately below water. Included in this relative scale is ethylene, which has an accurately determined proton affinity, allowing the determination of the proton affinity of water as 166.7 kcal mol-1