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arXiv · cond-mat/9708004

Ground States of Two-Dimensional Polyampholytes

Eilon Brenner·Yacov Kantor
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Abstract

We perform an exact enumeration study of polymers formed from a (quenched) random sequence of charged monomers $\pm q_0$, restricted to a 2-dimensional square lattice. Monomers interact via a logarithmic (Coulomb) interaction. We study the ground state properties of the polymers as a function of their excess charge $Q$ for all possible charge sequences up to a polymer length N=18. We find that the ground state of the neutral ensemble is compact and its energy extensive and self-averaging. The addition of small excess charge causes an expansion of the ground state with the monomer density depending only on $Q$. In an annealed ensemble the ground state is fully stretched for any excess charge $Q>0$.

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Eilon Brenner, Yacov Kantor. 1997-08-01. Ground States of Two-Dimensional Polyampholytes. https://doi.org/10.1103/physreve.56.5278

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