ON THE FRAGMENTATION OF HALOAROMATIC RADICAL-ANIONS AND THEIR ORBITALISOMERISM - A THEORETICAL-STUDY

We present a semiempirical theoretical study on the electronic nature of the radical anions of halobenzenes, nitrobenzyl halides, omicron-ha lodiphenyl sulfides and halophenyl-substituted cyclohexadienones (X = Cl, Br, I). The pi-sigma* radical anions (RAs) were localized as mini ma on the potential energy surface for the molecules under study with the exception of the nitrobenzyl halides for which a different behavio r was determined. Both RAs differ in their charge and unpaired spin di stribution, which is mainly located on the carbon-halogen bond for the sigma isomer. A good correlation between the experimental and theore tically predicted properties is obtained. This is the first report abo ut the localization of both isomeric RAs.