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A reciprocal structure (RS) is a mechanical resistant structure formed by a set of self-supporting elements satisfying certain conditions of structural reciprocity (SR) . The first condition is that each element of the structure has to support and be supported by the others. The second condition is that these functions cannot occur in the same part of the element. These two properties make beams and two-dimensional materials very much appropriate to build RSs. Commonly seen in floors or roofs, SR is also present in art, religious symbols and decorative objects. Da Vinci has drawn several examples of such RSs. Here, we propose a simple nano version of a da Vincis RS based on graphene nanoribbons. The stability and resistance against mechanical impacts (ballistic projectile) were investigated through fully atomistic molecular dynamics (MD) simulations. We considered structures with three and four joins with and without RS topologies. Our MD results showed that structures with RS topologies are more impact resistant than those without SR, despite the fact that the used graphene nanoribbons are highly pliable. We discuss these results in terms of the number of joins, energy absorption and stress on the structures. We discuss possible applications in nanoengineering.
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