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Soft elasticity of RNA gels and negative Poisson ratio

Amir Ahsan·Joseph Rudnick·Robijn Bruinsma
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Abstract

We propose a model for the elastic properties of RNA gels. The model predicts anomalous elastic properties in the form of a negative Poisson ratio and shape instabilities. The anomalous elasticity is generated by the non-Gaussian force-deformation relation of single-stranded RNA. The effect is greatly magnified by broken rotational symmetry produced by double-stranded sequences and the concomitant soft modes of uniaxial elastomers.

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Amir Ahsan, Joseph Rudnick, Robijn Bruinsma. 2005-12-18. Soft elasticity of RNA gels and negative Poisson ratio. https://arxiv.org/abs/cond-mat/0512423

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