title: Theoretical study of the stability of multiply charged C70 fullerenes.
abstract: We have calculated the electronic energies and optimum geometries of C(70) (q+) and C(68) (q+) fullerenes (q=0-14) by means of density functional theory. The ionization energies for C(70) and C(68) fullerenes increase more or less linearly as functions of charge, consistent with the previously reported behavior for C(60) and C(58) [S. Diaz-Tendero et al., J. Chem. Phys. 123, 184306 (2005)]. The dissociation energies corresponding to the C(70) (q+)-->C(68) (q+)+C(2), C(70) (q+)-->C(68) ((q-1)+)+C(2) (+), C(70) (q+)-->C(68) ((q-2)+)+C(+)+C(+), C(70) (q+)-->C(68) ((q-3)+)+C(2+)+C(+), and C(70) (q+)-->C(68) ((q-4)+)+C(2+)+C(2+) decay channels show that C(70) (q+) (like C(60) (q+)) is thermodynamically unstable for q>or=6. However, the slope of the dissociation energy as a function of charge for a given decay channel is different from that of C(60) (q+) fullerenes. On the basis of these results, we predict q=17 to be the highest charge state for which a fission barrier exists for C(70) (q+).
authors.affiliation: Departamento de Química, C-9, Universidad Autónoma de Madrid, 28049 Madrid, Spain. henning@physto.se
authors.forename: Henning
authors.initials: H
authors.lastname: Zettergren
authors.forename: Goar
authors.initials: G
authors.lastname: Sánchez
authors.forename: Sergio
authors.initials: S
authors.lastname: Díaz-Tendero
authors.forename: Manuel
authors.initials: M
authors.lastname: Alcamí
authors.forename: Fernando
authors.initials: F
authors.lastname: Martín