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arXiv · 2001.01745

Softening of DNA near Melting as Disappearance of an Emergent Property

Debjyoti Majumdar·Somendra M. Bhattacharjee
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Abstract

Near the melting transition the bending elastic constant, $\kappa$, an emergent property of double-stranded DNA (dsDNA), is shown not to follow the rod-like scaling for small length $N$. The reduction in $\kappa$ with temperature is determined by the denatured bubbles for a continuous transition, e.g., when the two strands are gaussian, but by the broken bonds near the open end in a Y-like configuration for a first-order transition as for strands with excluded volume interactions. In the latter case, a lever rule is operational implying a phase coexistence although dsDNA is known to be a single phase.

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Debjyoti Majumdar, Somendra M. Bhattacharjee. 2020-01-06. Softening of DNA near Melting as Disappearance of an Emergent Property. https://doi.org/10.1103/physreve.102.032407

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