Carbon clusters and fullerenes

Journal Article · Sat May 01 04:00:00 EDT 1993 · Bulletin of the American Physical Society

OSTI ID:281177

Compton, R N ^[1]

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1. Oak Ridge National Laboratory, TN (United States)

The electronic and ionic properties of small-to-large carbon clusters, including fullerenes, have been studied using surface ionization, multiphoton ionization (MPI), and alkali Rydberg charge exchange reactions. The negative ion properties of carbon clusters are of particular interest. Carbon clusters, C{sub n}, have been shown to form doubly charged negative ions for n {>=} 7. C{sub 60}{sup =} and C{sub 70}{sup =} seem to be especially stable. Rydberg charge exchange reactions with cold C{sub n} clusters show that C{sub 5}, C{sub 10}, C{sub 12}, C{sub 16}, and C{sub 18} have much larger low-energy electron attachment rates than other clusters. The MPI photoelectron spectrum of C{sub 60} shows prompt electrons resulting from direct two-photon ionization as well as dominant low-energy ({bar {epsilon}} = 0.32 eV) electron which occur for u sec after the laser pulse. Others have ascribed such {open_quotes}delayed{close_quotes} ionization to thermionic emission. We will also summarize research on mechanisms leading to laser and arc-discharge production of fullerenes as well as chemical modification of fullerenes, such as fluorination, hydrogenation, and coalescence (e.g. n{sm_bullet}C{sub 60} {yields} C{sub n} {sm_bullet} 60). Efforts to insert hydrogen atoms and molecules into C{sub 60} [e.g. catalytic reduction, hydrogen discharge, and high pressure (>1000 bar of H{sub 2})] reactions will be described.

• DOE Contract Number: AC05-84OR21400
• OSTI ID: 281177
• Report Number(s): CONF-9305421--
• Journal Information: Bulletin of the American Physical Society, Journal Name: Bulletin of the American Physical Society Journal Issue: 3 Vol. 38; ISSN BAPSA6; ISSN 0003-0503
• Country of Publication: United States
• Language: English

Related Subjects

66 PHYSICS
ELECTRONIC STRUCTURE
FULLERENES
IONIZATION
MULTI-PHOTON PROCESSES
SOLID CLUSTERS