Novel 2D PC₅ with a Dirac Cone and Edge-Size Dependence

2D materials with Dirac cones, which show a linear band character near the Fermi level, exhibit many novel properties. Herein, based on first-principles calculations, the 2D phosphorus carbide ((Formula presented.)) monolayer is studied systematically. The stability is examined by calculating the formation energy, phonon dispersion, and elastic constants as well as by performing ab initio molecular dynamics (AIMD) simulations. Due to the similarity of its structure to that of graphene, one Dirac cone is exactly located at the Fermi level, which is very robust against external biaxial and uniaxial strains. Treating the (Formula presented.) monolayer as graphene with doped P atoms along the armchair direction, a (Formula presented.) rule is found similar to that of graphene nanoribbons with armchair edges. These physical properties make the (Formula presented.) monolayer a promising 2D material for emerging electronics applications.