title: Formation of C60(2-) dianions in collisions between C60- and Na atoms.
abstract: We have observed the formation of C2-60 and C2-70 in collisions between C(-)(60)/C(-)(70) and Na atoms. Cross sections for the electron transfer to the monoanion are determined to be 36+/-9 and 57+/-14 A(2) for C-60 and C-70, respectively. A simple model investigation suggests that the electron is transferred from a Na atom to a low-lying electronic state of the fullerene to form a dianion. The method leads to pico-ampere energetic beams of C60 dianions that can be used for spectroscopy and lifetime studies.
authors.affiliation: Department of Physics and Astronomy, University of Aarhus, DK-8000 Aarhus C, Denmark.
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
authors.forename: Preben
authors.initials: P
authors.lastname: Hvelplund
authors.forename: Steen Brøndsted
authors.initials: SB
authors.lastname: Nielsen
authors.forename: Shigeo
authors.initials: S
authors.lastname: Tomita