The advantage of this scheme is that electrons behave as if they have no mass, resulting in energies that are proportional to the momentum of the electrons. Due to the Dirac cones, there is a single point in the Fermi level where the conduction and valence bands meet in a linear fashion. The models for graphyne show that it has the potential for Dirac cones on its double and triple bonded carbon atoms. Out of the theorized structures the rectangular lattice of 6,6,12-graphyne may hold the most potential for future applications. It has been hypothesized as preferable to graphene for specific applications due to the potential of direction-dependent Dirac cones. The proposed geometries include a hexagonal lattice structure and a rectangular lattice structure. This variety is due to the multiple arrangements of sp and sp2 hybridized carbon. Graphyne is theorized to exist in several different geometries. The proposed structures of graphyne are derived from inserting acetylene bonds in place of carbon-carbon single bonds in a graphene lattice. Graphyne has yet to be synthesized in significant quantities for study but through the use of computer models scientists have been able to predict several properties of the substance on assumed geometries of the lattice. The existence of graphyne was conjectured before 1960, and attracted attention after the discovery of fullerenes.Īlthough not yet synthesized, periodic graphyne structures and their boron nitride analogues were shown to be stable on the basis of first-principles calculations using phonon dispersion curves and ab-initio finite temperature, quantum mechanical molecular dynamics simulations. Depending on the content of acetylene groups, graphyne can be considered a mixed hybridization, sp n, where 1 < n < 2, and thus differs from the hybridization of graphene (considered pure sp 2) and diamond (pure sp 3). It can be seen as a lattice of benzene rings connected by acetylene bonds.
Its structure is one-atom-thick planar sheets of sp and sp 2-bonded carbon atoms arranged in crystal lattice. Graphyne is graphyne-1 graphdiyne is graphyne-2. Graphyne- n varieties, where n indicates the number of carbon-carbon triple bonds in a link between two adjacent hexagons.
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