Grazing incidence scattering of hyperthermal C-60(+), C-76(+), and C-84(+)from graphite: Electron transfer dynamics

Hyperthermal grazing. incidence scattering (E-coll = 500-700 eV, theta (in) = 80 degrees) of fullerenes C-60(+) C-76(+). and C-84(+) from highly orient ed pyrolytic graphite surfaces is associated with efficient one and two ele ctron transfer to yield parent neutrals and anions-in addition to parent ca tions. We report lower limits to nascent anion yields under conditions for which collisional heating is kept relatively small. Largest anion yields we re observed for C-84, which also has the largest electron affinity of the p rojectiles probed. Here >3% of the particles scattered upon 11500 ms(-1) co llision survive detection as anions. This can be qualitatively understood i n terms of a resonant electron transfer mechanism and a simple kinetic sche me. (C) 2001 American Institute of Physics.