Force driven transition of a globular polyelectrolyte.

摘要: We have systematically studied behavior of a flexible polyelectrolyte (PE) chain with explicit counterions, subjected to constant force at the terminal ends. Our simulations reveal that in hydrophobic regime, PE globule abruptly opens coil state beyond critical Fc. At transition point, polymer shape shows large scale fluctuations are quantified terms end-to-end distance Re. These suggest system coexists and states transition, which is also confirmed from bimodal distribution Moreover, associated exhibits nonmonotonic behavior, where surprisingly, Fc decreases Bjerrum length lB limit small lB, followed by an increase larger limit. Furthermore, this validated theory adopted for PE. From free energy analysis, we demonstrated predominantly, competition between intrachain repulsive energy, counterion's translational entropy, adsorption leads novel feature force.