New superhard tetragonal BCN from crystal chemistry and first principles

Novel ternary equiatomic BCN compound structurally based on the ‘glitter’ C6 with both tetrahedral (sp3) and trigonal (sp2) carbons has been predicted using crystal chemistry rationale supported by first principles calculations of energies energy dependent quantities within density functional theory (DFT). Crystal structure belongs to tetragonal space group P42mc is built stacking corner sharing BC2N2 tetrahedra. The phase found energetically cohesive stable mechanically (elastic properties) dynamically (phonons band structures). electronic structures reveal metallic-like behavior. Characterized very high Vickers hardness (65 GPa), expected be a prospective superabrasive.