Ab initio molecular orbital calculations have been carried out to obtain the structures and relative isomer energies of organometallic radical anions of the types CH₃X^–˙ and H₂C˙–XH^–(X = Li, BeH, BH₂, Na, MgH, or AlH₂). Comparison with results for the corresponding neutral molecules indicates a dramatic reduction in the energy gap between classical and hydrogen-shifted isomers on addition of an electron. However, the classical isomers of the radical anions generally represent the preferred form. The only exception is H₂C˙–BH₃^–, which is calculated to be virtually isoenergetic with H₃CBH₂^–˙. Organoborane radical anions are thus the most likely systems to adopt distonic structures with the formal charge and radical centres on different atoms. Further separation of the charge and the radical sites through homologation is predicted to be ineffective in stablising the distonic structures. MNDO calculations on larger models point to experimentally accessible distonic radical anions. The present study leads to a better understanding of the origin of distonic stablisation in radical ions.