Nanocomposites and nanomaterials

Influence of the force field on the height of energy barrier for carbyne-graphene nanoelements break
D. Petrovska1,2, S. Kotrechko1,2, N. Stetsenko2
1 Kyiv Academic University, Department of Applied Physics and Nanomaterials, Vernadsky Blvd., 36, Kyiv-03680, Ukraine.
E-mail: petrovska.d.r@gmail.com 
2 G.V. Kurdyumov Institute for Metal Physics, National Academy of Sciences of Ukraine, Vernadsky Blvd.,36, Kyiv-03680, Ukraine.

Carbyne (linear allotrope of Carbon) and carbyne-graphene nanoelements (graphene sheets connected by carbyne) are essential for a wide range of technologies. Stability and lifetime have a key role in the practical usage of carbyne and carbyne-graphene nanoelements. 
This paper shows the regularities of deformation and atomic bond breaking in carbyne of different lengths. Dependency between applied force and energy barrier height was established. It was shown that work of bond break reliance on length of chain could be properly described with Morse-type curve. Hence, the derivative of this dependency represents deformation curve. Consequently, analytical dependency between potential barrier height and applied force was obtained. This dependency appeared to be non-linear. Zhurkov theory, which is based on the linear dependency between bond breaking work and applied force, was proven as incorrect for nanostructures. It was shown, that the instability zone plays a crucial role in processes of deformation and bond breaking in carbyne chains.
The findings reported here provide a deeper insight into understanding the influence of the instability zone to the power consumption by breaking the carbyne chain. Dependencies for bond breaking work were established considering the instability zone. Regularities of the instability zone influence to different-length carbyne chains collapse were found.

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