title: What Is the Limit of Atom Encapsulation for Icosahedral Carboranes?
abstract: The stability of endohedral carboranes X@{1,n-C2B10H12} (X = Li(+), Be(2+); n = 2, 7, 12) and X@{CB11H12(-)} (X = Li(+), Be(2+)) is studied using electronic structure calculations with the B3LYP/6-311+G(d,p) model. Our calculations suggest that all endohedral compounds are local energy minima; for the exohedral complexes X···cage, the global energy minimum always corresponds to the X atom above a triangular face of the icosahedron. In the latter the X atom is furthest apart from the carbon atoms of the cage. As opposite to exohedral {Be(2+)···cage} complexes, no global energy minima were found for exohedral complexes {Li(+)···cage} whereby a carbon atom is present in the triangular face of the icosahedron below the Li(+) cation.
authors.affiliation: Instituto de Química-Física Rocasolano (CSIC), ES-28006 Madrid, Spain.|Instituto de Ciencia Molecular, Universidad de Valencia, ES-46100 Valencia, Spain.|Texas A&M University at Galveston, Galveston, Texas 77553-1675.
authors.forename: Vanesa
authors.initials: V
authors.lastname: Manero
authors.affiliation: Instituto de Química-Física Rocasolano (CSIC), ES-28006 Madrid, Spain.|Instituto de Ciencia Molecular, Universidad de Valencia, ES-46100 Valencia, Spain.|Texas A&M University at Galveston, Galveston, Texas 77553-1675.
authors.forename: Josep M
authors.initials: JM
authors.lastname: Oliva
authors.affiliation: Instituto de Química-Física Rocasolano (CSIC), ES-28006 Madrid, Spain.|Instituto de Ciencia Molecular, Universidad de Valencia, ES-46100 Valencia, Spain.|Texas A&M University at Galveston, Galveston, Texas 77553-1675.
authors.forename: Luis
authors.initials: L
authors.lastname: Serrano-Andrés
authors.affiliation: Instituto de Química-Física Rocasolano (CSIC), ES-28006 Madrid, Spain.|Instituto de Ciencia Molecular, Universidad de Valencia, ES-46100 Valencia, Spain.|Texas A&M University at Galveston, Galveston, Texas 77553-1675.
authors.forename: Douglas J
authors.initials: DJ
authors.lastname: Klein