title: Planar pentacoordinate carbons in CBe5(4-) derivatives.
abstract: The potential energy surfaces of a series of clusters with formula CBe5Lin(n-4) (n = 1 to 5) have been systematically explored. Our computations show that the lithium cations preserve the CBe5(4-) pentagon, such that the global minimum structure for these series of clusters has a planar pentacoordinate carbon (ppC) atom. The systems are primarily connected via a network of multicenter σ-bonds, in which the C atom acts as σ-acceptor and this acceptance of charge is balanced by the donation of the 2pz electrons to the π-cloud. The induced magnetic field analysis suggests that the clusters with formula CBe5Lin(n-4) (n = 1 to 5) are fully delocalized. The fact that these ppC-containing clusters are the lowest-energy forms on the corresponding potential energy surfaces raises expectations that these species can be prepared experimentally in the gas phase.
authors.affiliation: Departamento de Física Aplicada, Centro de Investigación y de Estudios Avanzados, Unidad Mérida, Km. 6 Antigua Carretera a Progreso, A.P. 73, Cordemex, Mérida 97310, Yucatán, México. gmerino@mda.cinvestav.mx.
authors.forename: Rafael
authors.initials: R
authors.lastname: Grande-Aztatzi
authors.forename: José Luis
authors.initials: JL
authors.lastname: Cabellos
authors.forename: Rafael
authors.initials: R
authors.lastname: Islas
authors.forename: Ivan
authors.initials: I
authors.lastname: Infante
authors.forename: José M
authors.initials: JM
authors.lastname: Mercero
authors.forename: Albeiro
authors.initials: A
authors.lastname: Restrepo
authors.forename: Gabriel
authors.initials: G
authors.lastname: Merino