Complete π-Electron Treatment of Allyl Radical and Allyl Ion

The wave functions for the allyl radical and ion are linear combinations of all independent antisymmetrized products of π-electron wave functions. The ground-state energy of the radical is 3W2p—28.963 ev and of the ion 2W2p—30.471 ev. Setting —W2p equal to the ionization energy of methyl, the ionization energy of allyl is calculated to be 8.44 ev, compared to an experimental value of 8.16 ev. The resonance energy of the ion is calculated to be ∼1.50 ev greater than that of the radical. An experimental comparison based on methyl and neglecting some compression energy is ∼1.70 ev.