The lowest electronic states of the benzoyl ion. A molecular orbital study with configuration interaction

Abstract

AbstractA configuration interaction method of molecular orbital theory shown to be accurate for the calculation of excited state energies in several aromatic systems was applied to the problem of excited states of the benzoyl ion. The excited singlet and triplet states of the benzoyl ion lie at least 3.8 eV and 2.6 eV, respectively, above the ground state. These results are not in agreement with a postulated state 20 kcal above the ground state. On the other hand, the charge distribution in excited states does agree with that postulated for the 20 kcal state. The p‐hydroxy and p‐cyano substituents do not greatly influence the charge distribution between the ring and the carbonyl group in either the ground or lowest excited states.