Double-electron transfer in H(-) + H(+) collisions.

Absolute cross sections for double-electron transfer in H(-) + H(+) collisions have been measured for center-of-mass energies from 0.5 to 12 keV. Clear oscillations in the cross section are observed shedding new light on earlier measurements.

Resonant Electron Transfer in Collisions between Two Fullerene Ions.

Fullerenes are a direct link between atoms with discrete electronic energy levels and solids with a band structure and a well-defined surface. In this Letter, we report on the first ever experiment on resonant electron transfer in collisions between two fullerene ions. Total cross sections have been measured for the reaction C+60+C2+60-->C2+60+C+60 at center-of-mass energies ranging from 27 to 69 keV.

Deep-core dielectronic-capture resonances in the electron-impact ionization of heavy atomic ions.

Experimental measurements and theoretical calculations are carried out for the electron-impact ionization of Sm(12+). The low energy region of the single ionization cross section for Sm(12+) is found to be dominated by contributions from the indirect process of excitation autoionization. At about 1.

Electron-impact induced fragmentation of fullerene ions.

The C2 fragmentation of fullerene ions C(q+)(60) (q = 1,2,3) induced by electron impact was studied for the first time. The cross sections for the loss of a C2 fragment indicate the presence of two different processes. At low electron energies the projectile electron leads to the direct excitation of the giant plasmon resonance.

Multiple ionization and fragmentation of negatively charged fullerene ions by electron impact.

Cross sections for the electron-impact multiple ionization and fragmentation of negatively charged fullerene ions C(-)(n) ( n = 60, 70) to C(q+)(n-m) ( q = 1,2,3 and m = 0,2,4) have been measured for electron energies up to 1 keV. In the case of pure ionization all threshold energies are about 10 eV higher than the values expected. This shift, however, is not observed for the fragment ions.