Theoretical enthalpy of formation of the acetonyl radical

The standard enthalpy of formation of the acetonyl radical (CH2COCH3) was theoretically estimated using several working chemical reactions, with four variants of theoretical approaches (levels) and four extended basis sets. Our best theoretical enthalpy of formation is ΔfH0298(CH2COCH3)=−32±4 kJ mol−1. This computed value corresponds to the bond dissociation energy of DH0298(H–CH2COCH3)=403±4 kJ mol−1, and to the resonance stabilization energy (RE0) and the intrinsic stabilization energy (SE0) of 16.5 and 14.2 kJ mol−1, respectively. These energies indicate a greater stabilization of the acetonyl radical than previously thought.