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We report the experimental and theoretical investigation of the growth and of the structure of large carbon clusters produced in a supersonic expansion by a pulsed microplasma source. The absence of a significant thermal annealing during the cluster growth causes the formation of disordered structures where sp2 and sp hybridizations coexist for particles larger than roughly 90 atoms. Among different structures we recognize sp2 closed networks encaging sp chains. This nutshell configuration can prevent the fragmentation of sp species upon deposition of the clusters thus allowing the formation of nanostructured films containing carbynoid species, as shown by Raman spectroscopy. Atomistic simulations confirm that the observed Raman spectra are the signature of the sp/sp2 hybridization characteristic of the isolated clusters and surviving in the film and provide information about the structure of the sp chains. Endohedral sp chains in sp2 cages represent a novel way in which carbon nanostructures may be organized with potential interesting functional properties.
We report the production and characterization of a form of amorphous carbon films with sp/sp2 hybridization (atomic fraction of sp hybridized species > 20%) where the predominant sp bonding appears to be (=C=C=)n cumulene. Vibrational and electronic
A novel form of amorphous carbon with sp-sp2 hybridization has been recently produced by supersonic cluster beam deposition showing the presence in the film of both polyynic and cumulenic species [L. Ravagnan et al. Phys. Rev. Lett. 98, 216103 (2007)
A structurally stable carbon allotrope with plentiful topological properties is predicted by means of first-principles calculations. This novel carbon allotrope possesses the simple space group C2/m, and contains simultaneously sp, sp2 and sp3 hybrid
We have characterized the frictional properties of nanostructured (ns) carbon films grown by Supersonic Cluster Beam Deposition (SCBD) via an Atomic Force-Friction Force Microscope (AFM-FFM). The experimental data are discussed on the basis of a modi
Graphdiyne, atomically-thin 2D carbon nanostructure based on sp-sp2 hybridization, is an appealing system potentially showing outstanding mechanical and optoelectronic properties. Surface-catalyzed coupling of halogenated sp-carbon-based molecular pr