Lifetimes of metastable spherical carbon cluster dianions

Abstract

Semiclassical calculations are made of the lifetimes of metastable spherical carbon cluster dianions using a model potential based on electrostatics. The metastability is attributed to shape resonances resulting from the combination of the long range Coulomb repulsion and the shorter range electron-molecule interaction. Results for fullerene dianions show a strong dependence of the lifetimes on the molecular size. The transition from stable to metastable dianions is estimated to occur when the radius of the spherical molecule is about 5.5 Å. This simple model potential might provide a starting point for experimental and theoretical searches for the existence of stable dianions