title: Sc2(mu2-O) trapped in a fullerene cage: the isolation and structural characterization of Sc2(mu2-O)@C(s)6-C82 and the relevance of the thermal and entropic effects in fullerene isomer selection.
abstract: The new endohedral fullerene, Sc(2)(mu(2)-O)@C(s)(6)-C(82), has been isolated from the carbon soot obtained by electric arc generation of fullerenes utilizing graphite rods doped with 90% Sc(2)O(3) and 10% Cu (w/w). Sc(2)(mu(2)-O)@C(s)(6)-C(82) has been characterized by single crystal X-ray diffraction, mass spectrometry, and UV/vis spectroscopy. Computational studies have shown that, among the nine isomers that follow the isolated pentagon rule (IPR) for C(82), cage 6 with C(s) symmetry is the most favorable to encapsulate the cluster at T > 1200 K. Sc(2)(mu(2)-O)@C(s)(6)-C(82) is the first example in which the relevance of the thermal and entropic contributions to the stability of the fullerene isomer has been clearly confirmed through the characterization of the X-ray crystal structure.
authors.affiliation: Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, USA.
authors.forename: Brandon Q
authors.initials: BQ
authors.lastname: Mercado
authors.forename: Melissa A
authors.initials: MA
authors.lastname: Stuart
authors.forename: Mary A
authors.initials: MA
authors.lastname: Mackey
authors.forename: Jane E
authors.initials: JE
authors.lastname: Pickens
authors.forename: Bridget S
authors.initials: BS
authors.lastname: Confait
authors.forename: Steven
authors.initials: S
authors.lastname: Stevenson
authors.forename: Michael L
authors.initials: ML
authors.lastname: Easterling
authors.forename: Ramón
authors.initials: R
authors.lastname: Valencia
authors.forename: Antonio
authors.initials: A
authors.lastname: Rodríguez-Fortea
authors.forename: Josep M
authors.initials: JM
authors.lastname: Poblet
authors.forename: Marilyn M
authors.initials: MM
authors.lastname: Olmstead
authors.forename: Alan L
authors.initials: AL
authors.lastname: Balch