Phase diagram of flexible polymers with quenched disordered charged monomers.
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Data
2022
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Resumo
Recent advances in Generalized Ensemble simulations and microcanonical analysis
allowed the investigation of structural transitions in polymer models over a broad
range of local bending and torsion strengths. It is reasonable to argue that electrostatic
interactions play a significant role in stabilizing and mediating structural transitions in
polymers. We propose a bead–spring polymer model with randomly distributed charged
monomers interacting via a screened Coulomb potential. By combining the Replica
Exchange Wang–Landau (REWL) method with energy-dependent monomer updates, we
constructed the hyperphase diagram as a function of temperature (T ) and charged
monomer concentration (η). The coil–globule and globular–solid transitions are second
and first order for the entire concentration range. However, above a concentration
threshold of η = 80%, electrostatic repulsion hinders the formation of solid and
liquid globules, and the interplay between enthalpic and entropic interactions leads
to the formation of liquid pearl-necklace and solid helical structures. The probability
distribution, P(E, T ), indicates that at high η, the pearl-necklace liquid phase freezes
into a stable solid helix-like structure with a free energy barrier higher than the freezing
globule transition at low η.
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Replica exchange Wang–Landau, Diluted polymer, Phase transitions, Microcanonical analysis
Citação
RODRIGUES, B. B. et al. Phase diagram of flexible polymers with quenched disordered charged monomers. Physica A, v. 604, artigo 127787, 2022. Disponível em: <https://www.sciencedirect.com/science/article/pii/S0378437122005192>. Acesso em: 06 jul. 2023.