Confinement and controlling the effective compressive stiffness of carbyne

Carbyne is a one-dimensional chain of carbon atoms, consisting of repeating sp -hybridized groups, thereby representing a minimalist molecular rod or chain. While exhibiting exemplary mechanical properties in tension (a 1D modulus on the order of 313 nN and a strength on the order of 11 nN), its use as a structural component at the molecular scale is limited due to its relative weakness in compression and the immediate onset of buckling under load. To circumvent this effect, here, we probe the effect of confinement to enhance the mechanical behavior of carbyne chains in compression. Through full atomistic molecular dynamics, we characterize the mechanical properties of a free (unconfined chain) and explore the effect of confinement radius ( R ), free chain length ( L ) and temperature ( T ) on the effective compressive stiffness of carbyne chains and demonstrate that the stiffness can be tuned over an order of magnitude (from approximately 0.54 kcal mol −...

Ashley J Kocsis, Neta Aditya Reddy Yedama and Steven W Cranford

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