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

Brandon Q Mercado; Melissa A Stuart; Mary A Mackey; Jane E Pickens; Bridget S Confait; Steven Stevenson; Michael L Easterling; Ramón Valencia; Antonio Rodríguez-Fortea; Josep M Poblet; Marilyn M Olmstead; Alan L Balch

doi:10.1021/ja104902e

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

J Am Chem Soc. 2010 Sep 1;132(34):12098-105. doi: 10.1021/ja104902e.

Authors

Brandon Q Mercado¹, Melissa A Stuart, Mary A Mackey, Jane E Pickens, Bridget S Confait, Steven Stevenson, Michael L Easterling, Ramón Valencia, Antonio Rodríguez-Fortea, Josep M Poblet, Marilyn M Olmstead, Alan L Balch

Affiliation

¹ Department of Chemistry, University of California, One Shields Avenue, Davis, California 95616, USA.

PMID: 20698534
DOI: 10.1021/ja104902e

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.