A single coarse-grained polymer chain and salt ions are placed into a cubic simulation box to prepare 0.0 m (counterions only), 0.1 m, 0.4 m, 1.0 m and 2.0 m salt solvation environment. Periodic boundary conditions are applied. The default volume of the simulation box 8304 nm 3 is reduced to one fourth when the polymer holds a compact globular conformation and the salt concentration is ≥ 1 m. The compositions of the systems are described in detail in Table . A trajectory of 525 ns is obtained in every simulation run. The initial 25 ns is considered as an equilibration phase and thus excluded from the analysis. Standard Gromacs tools, namely gmx polystat and gmx rdf, are used for the data analysis. Further statistical evaluations are performed in R. The uncertainties of the quantities are determined as a standard error obtained from ten independent parts of the simulation trajectory.