Structural stabilities and electronic properties of planar C4 carbon sheet and nanoribbons
Abstract
By means of first-principles calculations, we theoretically studied the structural stabilities and electronic properties of a pure-carbon 2D covalent metal named planar C4 in P4/mmm (D14h) symmetry. Planar C4 is confirmed to be dynamically stable in the ground state based on phonon-mode analysis, and it is more stable than graphyne and the recently prepared graphdiyne. Moreover, it has a higher density of states (DOS) at the Fermi level than any plausible metallic