title: Structure and thermodynamics of carbon and carbon/silicon precursors to nanostructures.
abstract: The structures at the Hartree-Fock level, as well as the energetics, are reported for the unsaturated system C(36)H(16), its Si-doped analogue C(32)Si(4)H(16), and several smaller, unsaturated fragments. Structural effects on the electronic distribution are discussed in terms of a localized orbital energy decomposition. The standard heats of formation are calculated based on homodesmic and isodesmic reactions and the G2(MP2,SVP) method with a valence double-zeta plus polarization basis. The origin of the observed explosion of the all-carbon system (C(36)H(16)) to form carbon nanotubes was investigated by exploring a possible initial reactive channel (dimerization), which could lead to the formation of the observed onion-type nanostructures.
authors.affiliation: San Diego Supercomputer Centre, University of California San Diego, 9500 Gilman Drive, MC0505, La Jolla, California 92093-0505, USA.
authors.forename: Vassiliki-Alexandra
authors.initials: VA
authors.lastname: Glezakou
authors.forename: Jerry A
authors.initials: JA
authors.lastname: Boatz
authors.forename: Mark S
authors.initials: MS
authors.lastname: Gordon