PolyRingene: A novel 2D carbon allotrope explored via first-principles and machine learning interatomic potentials

Abstract

We report the computational design and characterization of PolyRingene, a novel two-dimensional carbon allotrope with a lattice composed of 3-, 4-, 5-, 6-, 8-, and 10-membered rings. First-principles calculations confirm the energetic, dynamical, and thermal stability of this material through phonon dispersion and ab initio molecular dynamics simulations. Electronic structure analysis reveals a metallic character. Mechanical response under uniaxial strain shows anisotropy, with Young’s modulus of 610 GPa along the x-direction and 560 GPa along the y-direction. Fracture occurs at 12% strain, accompanied by the formation of linear atomic carbon chains that bridge the ruptured regions. To enable large-scale simulations, we developed a machine learning interatomic potential (MLIP) trained on density functional theory data. The MLIP accurately reproduces phonon spectra and stress–strain responses, outperforming traditional empirical potentials and demonstrating excellent transferability.