title: Theoretical predictions of a bucky-diamond SiC cluster.
abstract: A study  of structural relaxations of Si(n)C(m) clusters corresponding to different compositions, different relative arrangements of Si/C atoms, and different types of initial structure, reveals that the Si(n)C(m) bucky-diamond structure can be obtained for an initial network structure constructed from a truncated bulk 3C-SiC for a magic composition corresponding to n = 68 and m = 79. This study was performed using a semi-empirical Hamiltonian (SCED-LCAO) since it allowed an extensive search of different types of initial structures. However, the bucky-diamond structure predicted by this method was also confirmed by a more accurate density functional theory (DFT) based method. The bucky-diamond structure exhibited by a SiC-based system represents an interesting paradigm where a Si atom can form three-coordinated as well as four-coordinated networks with carbon atoms and vice versa and with both types of network co-existing in the same structure. Specifically, the bucky-diamond structure of the Si(68)C(79) cluster consists of a 35-atom diamond-like inner core (four-atom coordinations) suspended inside a 112-atom fullerene-like shell (three-atom coordinations).
authors.affiliation: Department of Physics and Astronomy, University of Louisville, KY 40292, USA. m0yu0001@louisville.edu
authors.forename: Ming
authors.initials: M
authors.lastname: Yu
authors.forename: C S
authors.initials: CS
authors.lastname: Jayanthi
authors.forename: S Y
authors.initials: SY
authors.lastname: Wu
mesh_terms: D017554:Carbon Compounds, Inorganic; D003198:Computer Simulation; D018130:Diamond / Q000737:chemistry*; D037741:Fullerenes / Q000737:chemistry*; D046911:Macromolecular Substances / Q000737:chemistry; D008956:Models, Chemical; D008958:Models, Molecular; D008968:Molecular Conformation; D049329:Nanostructures / Q000737:chemistry* / Q000648:ultrastructure*; D010316:Particle Size; D017655:Silicon Compounds; D013499:Surface Properties
chemical_list: D017554:Carbon Compounds, Inorganic; D037741:Fullerenes; D046911:Macromolecular Substances; D017655:Silicon Compounds; D018130:Diamond; C022088:silicon carbide