Ne++C60 collisions: The dynamics of charge and energy transfer, fragmentation, and endohedral complex formation

Abstract

Interaction of Ne+ with C60 has been studied for collision energies ranging up to 100 eV. The dominant process is charge transfer, with C60 + accounting for 85% to 100% of the total product signal in this energy range. At 25 eV collision energy, C60‐2n + dissociative charge transfer products appear, accounting for ∼13% of the total product signal at high energies. At ∼25 eV, NeC60 +, NeC58 +, and NeC56 + all appear together, followed by a series of NeC60‐2n + products where n increases with increasing collision energy. These products are believed to be endohedral complexes, Ne@C60‐2n +, where neon is physically trapped inside the fullerene cage. The production efficiency of the endocomplexes reaches a maximum of ∼1.2% at 60 eV, and decreases to 0.5% at 100 eV. Modeling the results leads to the following picture of Ne++C60 collision dynamics: Charge transfer occurs in nearly all collisions, and is the only significant process for high impact parameters. At collision energies below ∼25 eV, translational‐to‐internal energy transfer is inefficient, even for low impact parameter collisions. At higher energies, the inelasticity jumps to near 100%, leading to fragmentation of the nascent products. Both endohedral penetration and efficient energy transfer appear to require bond rupture in the C60.