The structure and properties of layered polymorphic types of diamond, so-called binary diamond-like layers (DLs), have been simulated by quantum-mechanical methods. These diamond-like layers consist of completely polymerized bilayer graphenes L-6, L4-8, L3-12, L4-6-12, and L5-7. Calculations based on a method of the density functional theory demonstrate that diamond-like DLs can be prepared by subjecting initial bilayer graphenes to strong uniaxial compression normally to the axis of these layers in the pressure range 8.6-51.4 GPa. If graphene layers consisting of topological defects are used as precursors, the phase transition pressure drops several-fold compared with normal graphene L-6. The L4-6-12 DL has a minimal layer density (0.98 mg/m(2)) and maximal pore diameter (4.56 angstrom). Unlike graphene and diamond, all DLs are expected to be semiconductors with a direct band gap of 1.36-2.38 eV. It has been found by means of molecular dynamics simulation that DLs DL6, DL4-8, DL4-6-12, and DL5-7 under normal pressure can be stable at 300 K, where the DL3-12 is expected to be unstable above 260 K. The most stable diamond-like DL, DL6, and a 3D phase on its basis are expected to offer a high mechanical performance. In synthesized carbon materials, this DL can be uniquely identified from a theoretical Raman spectrum and an X-ray absorption spectrum.
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