Extended carbon nanocones derived from non-graphene two-dimensional allotropes: A combined DFT and molecular dynamics...

We report a combined density functional theory (DFT) and reactive molecular dynamics investigation of extended carbon nanocones (xCNCs) derived from non-graphene two-dimensional carbon allotropes. Four precursor monolayers were investigated: acepentalene, naphthylene, r469-New20, and r568 lattices. Fifteen nanocone structures with disclination angles of 60°, 120°, and 180° were constructed and fully optimized at the GGA-PBE/DNP level. All structures were confirmed as true minima through vibrational frequency analysis. The calculated binding energies per carbon atom range from -6.82 to -7.55eV, comparable to C₆₀ fullerene (-7.56eV), indicating high thermodynamic stability. HOMO-LUMO gaps span 0.030 to 1.045 eV, demonstrating tunable semiconducting behavior dependent on precursor material and disclination angle. Thermodynamic analysis reveals that several xCNCs exhibit negative Gibbs free energies at 825-1000 K, suggesting thermodynamic feasibility for high-temperature synthesis. Reactive molecular dynamics simulations using the AIREBO potential confirm thermal stability at 600 K, with energy fluctuations below 0.12% over 50 ps production runs. Frontier orbital analysis shows characteristic spatial separation between edge-localized HOMOs and apex-localized LUMOs. These findings demonstrate that extended carbon nanocones represent viable targets for experimental synthesis with applications in nanoelectronics, catalysis, and sensing.