Calculation of the Heats of Formation of Gaseous Free Radicals and Ions

A simple method of calculating the heats of formation of gaseous free radicals and carbonium ions is presented, and a number of examples are given which show good agreement of calculated values with experiment. It is shown that the method permits ready calculation of bond strengths, including the strength of bonds in alicyclics, and the ionization potential of olefins, aromatics, and other unsaturates. The method is not directly applicable to the calculation of the ionization potentials of saturates.