  Studies aimed at designing new allotropic forms of carbon have received much
attention. Recently, a new 2D graphene-like allotrope named Pentahexoctite was
theoretically proposed. Pentahexoctite has a metallic signature, and its
structure consists of continuous 5-6-8 rings of carbon atoms with sp2
hybridization. Here, we carried out fully-atomistic computational simulations,
combining reactive (ReaxFF) molecular dynamics (MD) and density functional
theory (DFT) methods, to study the elastic properties and fracture patterns of
Pentahexoctite monolayer. Results revealed a Young's Modulus of 0.74 TPa,
smaller than the graphene one (about 1.0 TPa). The Pentahexoctite monolayer,
when subjected to a critical strain, goes directly from elastic to completely
fractured regimes. This process occurs with no plasticity stages between these
two regimes. Importantly, graphene presents a similar fracture process. The
elastic properties calculated with both DFT and MD are in good agreement.
Keywords: Reactive Molecular Dynamics, DFT, Mechanical Properties, Carbon
Allotrope,
