Freezing and Collapse of Flexible Polymers on Regular Lattices in Three Dimensions

TL;DR

This study investigates the crystallization and collapse transitions of flexible polymers on 3D lattices, revealing that these transitions remain separate in the thermodynamic limit due to the short-range interactions.

Contribution

It provides new insights into the distinct nature of polymer transitions on lattice models, contrasting with previous bond-fluctuation models.

Findings

Crystallization and collapse transitions stay separate at large chain lengths.

Short-range interactions influence the separation of transitions.

Results differ from bond-fluctuation polymer models.

Abstract

We analyze the crystallization and collapse transition of a simple model for flexible polymer chains on simple cubic and face-centered cubic lattices by means of sophisticated chain-growth methods. In contrast to bond-fluctuation polymer models in certain parameter ranges, where these two conformational transitions were found to merge in the thermodynamic limit, we conclude from our results that the two transitions remain well-separated in the limit of infinite chain lengths. The reason for this qualitatively distinct behavior is presumably due to the ultrashort attractive interaction range in the lattice models considered here.