相关论文: Tricarbon: two novel ultra-hard metallic carbon al…
A novel carbon allotrope, hexagonal C12, is proposed from crystal chemistry and quantum density functional theory DFT calculations of ground state and physical properties. The structure exhibits corner sharing distorted tetrahedra with the…
A new ultra-hard rhombohedral carbon rh-C4 (or hexagonal h-C12) is reported as derived from 3R graphite through crystal chemistry construction and ground state energy within the density functional theory. An extended hexagonal…
From crystal chemistry rationale and density functional DFT calculations, novel tetragonal carbon C5 is proposed as simplest ultrahard allotrope with mixed hybrid carbon hybridizations (sp2 - sp3). Novel pentacarbon is identified as…
Rhombohedral dense forms of carbon, rh-C2 (or hexagonal h-C6), and boron nitride, rh-BN (or hexagonal h-B3N3), are derived from rhombohedral 3R graphite based on original crystal chemistry scheme backed with full cell geometry optimization…
Novel high symmetry body centered carbon allotropes: cubic C48 and tetragonal C32 are proposed with respective original ana and ukc topologies. Devised from crystal structure engineering, their ground state structures and energy derived…
A sp2-sp3 hybrid carbon allotrope named HSH-carbon is proposed by the first-principles calculations. The structure of HSH-carbon can be regarded as a template polymerization of [1.1.1]propellane molecules in a hexagonal lattice, as well as,…
Superstructures of cubic and hexagonal diamonds (h- and c-diamond) comprising a family of stable diamond-like $sp^3$ hybridized novel carbon allotropes are proposed, which are referred to as U$_n$-carbon where $n \geq 2$ denotes the number…
Novel ultra-hard carbon allotrope is proposed with mechanical, dynamic, and thermal properties like diamond. Based on energy criteria from computations within density functional theory DFT, tetragonal C8 stoichiometry is identified as a…
The lon topology inherent to lonsdaleite C4 hexagonal diamond is shown to characterize three original carbon allotropes C8 in the orthorhombic system with irregular orientations of the C4 tetrahedra. The octacarbon stoichiometries were…
Two novel three-dimensional (3D) crystal structures of carbon (C) and germanium carbide (GeC2) were predicted using first-principles density-functional theory (DFT) calculations. These newly discovered 3D carbon allotrope and GeC2 are in…
Carbon enjoys a vast number of allotropic forms, each possessing unique properties determined by the lattice structures and bonding characters. Here, based on first-principles calculations, we propose a new three-dimensional carbon…
Four sp3 carbon allotropes with six, eight, and 16 atoms per primitive cell have been derived using a combination of metadynamics simulations and topological scan. A chiral orthorhombic phase oC16 (C2221) was found to be harder than…
New ultra-hard rhombohedral B2N2 and BC2N - or hexagonal B6N6 and B3C6N3 - are derived from 3R graphite based on crystal chemistry rationale schematizing a mechanism for 2D => 3D transformation. Full unconstrained geometry optimizations…
Original carbon allotropes C12 and C16 called superglitter and squarodiamond from relationships with literature glitter and squaroglitter respectively are shown through DFT-based geometry to be cohesive with energy dependent properties as…
Two mechanisms of changes from 2D to 3D (D = dimensionality) involving 2D C(sp2) trigonal paving to C(sp3) tetrahedral stacking are proposed through puckering of the 2D layers on one hand and interlayer insertion of extra C on the other…
Using a generalized genetic algorithm, we propose four new sp3 carbon allotropes with 5-6-7 (5-6-7-type Z-ACA and Z-CACB) or 4-6-8(4-6-8-type Z4-A3B1 and A4-A2B2) carbon rings. Their stability, mechanical and electronic properties are…
A structurally stable crystalline carbon allotrope is predicted by means of the first-principles calculations. This allotrope can be derived by substituting each atom in diamond with a carbon tetrahedron, and possesses the same space group…
Clathrates are lightweight, cage-like, fully-sp3 three dimensional (3D) structures that are experimentally-available for several host elements of the IV group. However, carbon clathrates are as yet hypothetical structures. Herein, the…
Based on C8, carbon 4C, with cfc topology, two hybrid carbon allotropes generated by inserting C(sp2) and C(sp1) carbon atoms into C8 diamond-like lattice were identified and labeled ene-C10 containing C(sp2) and ene-yne-C14 containing…
Two new carbon allotropes (H-carbon and S-carbon) are proposed, as possible candidates for the intermediate superhard phases between graphite and diamond obtained in the process of cold compressing graphite, based on the results of…