On the mechanical properties of novamene: a fully atomistic molecular dynamics and DFT investigation

TL;DR

This study uses atomistic molecular dynamics and DFT simulations to explore the mechanical properties and fracture behavior of novamene, a novel 3D carbon allotrope, revealing its anisotropic strength, strain, and unique fracture mechanisms.

Contribution

It provides the first detailed atomistic analysis of novamene's mechanical properties and fracture dynamics, highlighting its unique anisotropic behavior and self-healing features.

Findings

Novamene exhibits anisotropic tensile deformation.

It has the highest ultimate strain (~22.5%) along the z-direction.

It forms long carbon chains during fracture.

Abstract

We have investigated through fully atomistic reactive molecular dynamics and DFT simulations, the mechanical properties and fracture dynamics of novamene, a new 3D carbon allotrope structure recently proposed. Our results showed that novamene is an anisotropic structure with relation to tensile deformation. Although novamente shares some mechanical features with other carbon allotropes, it also exhibits distinct ones, such as, extensive structural reconstructions (self-healing effect). Novamene presents ultimate strength (~ 100 GPa) values lower than other carbon allotropes, but it has the highest ultimate strain along the z-direction (~ 22.5%). Although the Young's modulus (~ 600 GPa) and ultimate strength values are smaller than for other carbon allotropes, they still outperform other materials, such as for example silicon, steel or titanium alloys. With relation to the fracture dynamics, novamene is again anisotropic with the fracture/crack propagation originating from deformed heptagons and pentagons for x and y directions and broken sp3 bonds connecting structural planes. Another interesting feature is the formation of multiple and long carbon linear chains in the final fracture stages.