Density functional theory study of multiply ionized weakly bound fullerene dimers

Abstract

Multiply ionized fullerene dimers ([C(60)](2) (q+),q=1-6) have been studied by means of state-of-the-art density functional theory methods. We found that the singly charged dimer is more strongly bound than the corresponding neutral van der Waals dimer at the binding distance of the latter; in contrast, multiply charged dimers (q>or=2) are unstable. For the latter dimers, the calculated kinetic energy release in the binary fission yielding intact fullerenes is lower than those reported in recent experimental work. This implies that, in such experiments, there are significant internal excitations in the separating monomers. We also show that electron transfer within the charged dimers occurs on the subfemtosecond time scale, in accordance with the high charge mobility observed in dimers and larger clusters of fullerenes. This provides an explanation for the even-odd effects in the measured multiple ionization yields of fullerene dimers.

Magic and hot giant fullerenes formed inside ion irradiated weakly bound C60 clusters

“…20 A key aspect here is that ͑charged͒ clusters of fullerenes, in contrast to, e.g., weakly bound argon clusters, 21 are excellent electrical conductors 20 within which the charge is distributed on subfemtosecond time scales. 22,23 Thus, a Xe 20+ ion may, e.g., pass closely outside a ͓C 60 ͔ m surface and initially removes many electrons from individual C 60 molecules and then also excites them strongly. These charges spread out before the C 60 + are emitted from the cluster ͑pico-second timescales͒ and these fullerenes may also fragment but on even longer time scales ͑nano-to microseconds typically͒.…”

Formations of DumbbellC118andC119inside Clusters ofC60Zettergren1, Rousseau2, Wang3 et al. 2013Phys. Rev. Lett.652480View full textAdd to dashboardCite

“…2). The reason is that the electronic excitation energy is distributed rapidly [25,26] over the whole cluster before fragmentation such that the individual molecules most often become sufficiently cold to stay intact [17].…”

Ions colliding with clusters of fullerenes—Decay pathways and covalent bond formations

“…1. It has been established earlier that charge redistributes very rapidly within ionized clusters of C 60 molecules 21,22 and that the Coulomb explosion heats the individual molecules strongly.…”

“…With larger clusters, the C + 60−2m fragments become weaker in relation to the C + 60 peak and this is readily explained as larger clusters give a more effective cooling of the individual molecules as locally induced excitation energy and charge are distributed on the whole cluster before fragmentation. 22, 24 The C + 61 peak is present for small and large clusters but in the case of large n (Fig. 3) it is also accompanied by a significant C There, the details of general bottomup fullerene formation mechanisms were discussed and the inclusion of single C-atoms and single C 2 -molecules in C 60 was considered to be a crucial step.…”

“…Clusters of fullerenes are weakly bound with dissociation energies (E d ) of about 0.3 eV, 22 and they form evaporative ensembles at rather low temperatures (T evap ). In a simple Arrhenius type decay picture, 29 …”