A semi-flexible attracting-segment model of three-dimensional polymer collapse

TL;DR

This paper extends a 2D self-attracting polymer model to three dimensions, revealing two anisotropic collapsed phases with first-order transitions, and no disordered liquid-like phase.

Contribution

It introduces a semi-flexible attracting-segment model in three dimensions, showing the absence of a disordered collapsed phase and characterizing the nature of phase transitions.

Findings

Identifies two anisotropic collapsed phases in 3D

All phase transitions are first order

No disordered liquid-like collapsed phase

Abstract

Recently it has been shown that a two-dimensional model of self-attracting polymers based on attracting segments with the addition of stiffness displays three phases: a swollen phase, a globular, liquid-like phase, and an anisotropic crystal-like phase. Here, we consider the attracting segment model in three dimensions with the addition of stiffness. While we again identify a swollen and two distinct collapsed phases, we find that both collapsed phases are anisotropic, so that there is no phase in which the polymer resembles a disordered liquid drop. Moreover all the phase transitions are first order.