Deuterium isotope effect on the electron spin resonance spectrum of the cyclopentadienyl radical
Abstract
The e.s.r. spectrum shows that, in the radical C5H4D·, the unpaired electron occupies the ψA and ψS molecular orbitals with the probability 0·515: 0·485, which is consistent with a model which assumes a vibrational perturbation of the Hückel resonance integral β.