Experimental determination of the Compton profile of C60 through binary encounter electron spectroscopy

Moretto-Capelle

J. Phys. B: At. Mol. Opt. Phys.

et al. 2000

The electron spectrum produced in a low velocity collision between a multicharged ion and a C 60 molecule is measured for the first time. Its structure looks like that of electron spectra measured with heavy atomic targets, but lines coming from the autoionization of doubly-excited states of O 6+ ions are superimposed on a much more intense continuous background, strongly peaked at low electron energies. Double capture is found to occur into the 6lnl (n = 6 to 12) and 7lnl (n = 7 to 11) Rydberg series. Capture of three and four electrons is also briefly discussed. Help in the identification of the reactions is given by separate energy gain measurements. A time-offlight spectrum of the target ions measured in coincidence with low energy electrons (E e < 10 eV) shows that the production of these electrons is often accompanied by a C 60 cage destruction.

supporting

confidence: 70%

Hollow ion formation studied by electron spectroscopy of¹⁸O⁸⁺-C₆₀at 4.4 keV/amu*

Moretto-Capelle

J. Phys. B: At. Mol. Opt. Phys.

et al. 2000

“…It was suggested that the GDPR has a profound influence on the energy loss of the projectile. However, most of these studies were focused on measuring the GDPR contribution on the recoil-ion yields, whereas the electronspectroscopy-based measurements using a free C 60 molecule as the target are rather limited [9,[34][35][36][37]. This lack of experimental investigations on electron spectroscopy of C 60 can be, in part, attributed to the difficulties in detecting low-energy electrons.…”

Section: Introductionmentioning

confidence: 96%

Angle-differential observation of plasmon electrons in the double-differential cross-section spectra of fast-ion-induced electron ejection fromC60

2015

We report on the measurement of double-differential distribution of soft electron emission from C 60 fullerene, induced by a fast-moving Coulomb field of 76 MeV energy bare fluorine ions. A broad "plasmon-electron" peak, riding on the Coulomb-ionization continuum, is observed due to the deexcitation of the giant dipole plasmon resonance state in C 60 . The angular distribution of the plasmon electrons goes through a dip around 90• , which is contrary to that observed in ion-atom collisions measured in situ, indicating the alignment of the induced dipole moment along the projectile beam direction. A model based on the photoelectron angular distribution which is modified due to the ion-induced postcollisional interaction provides an excellent agreement with the observed asymmetric distribution. The distribution smoothly changes from a dip at 90• to a peak with the variation of ejected electron energy indicating transition from a collective plasmon behavior of the whole system to a single ion-atom interaction. The single-differential cross section was also derived, which preserves the signature of the collective excitation.

J. Phys.: Condens. Matter

“…Though the relative difference is rather small, the experiment clearly favours the C 60 calculation. We mention that recent Compton profile data obtained from the measurement of the binary-encounter electron peak in 18 MeV C 6+ /C 60 collisions [36] did not reveal any difference between a C 60 and a graphite Compton profile. We emphasize that the comparison of figure 7 and figure 6 relies on the fact that the graphite target, in particular, had spherically distributed crystallites.…”

Section: Resultsmentioning

confidence: 67%

Three-dimensional electron momentum densities of graphite and fullerene: a comparison

Metz

Tschentscher

Suortti

et al. 1999

We report on the three-dimensional electron momentum densities (EMD) of graphite and fullerene obtained by a so-called (,e) experiment, i.e. the coincident detection of an inelastically scattered hard x-ray photon with its recoil electron. A monochromatized flux of 1012 photons s-1 at 150 keV from the high-energy x-ray wiggler beamline of the ESRF was directed onto thin graphite or fullerene targets. Comparison with a pseudopotential and a full-potential linear muffin-tin orbital calculation in the case of graphite is made. Inclusion of electron correlation via the Lam-Platzman correction is discussed. The experimental EMD of C60 shows stronger electron delocalization in the `buckyball' compared to graphite, which is supported by theory.