Thermodynamic Properties of Star Shaped Polymers Investigated with Wang‐Landau Monte Carlo Simulations

Abstract

Entropic sampling method within Wang-Landau algorithm is used for simulation of lattice models of linear polymer chains and 6-arm star-shaped polymers. The semi-phantom (i.e. nonreversal) random walk on 3D simple cubic lattice is used as a reference system. The densities of states are obtained and on their basis the temperature dependences of internal energy, heat capacity, entropy and mean square radius of gyration are calculated. Results for stars are compared with data for linear chains.

Entropic sampling of star-shaped polymers with different number of arms: temperature dependencies of structural properties

“…This method was successfully applied in our previous works [13,15,[19][20][21] as well as by other authors [4,12,[22][23][24] in polymer studies. An important attractive feature of this method is in its ability to obtain statistics for very rare events with relative ease.…”

“…f =2, N arm =36) has been considered. The case with a fixed number of arms (f =6) was studied earlier in [19][20][21]. Fig.…”

“…7. Temperature dependencies of the asphericity δ (a) and of the parameter S * characterizing the form (b), for five 6-arm stars with varying arm lengths (N arm =5, 8,12,16,20). Symbols in lines are used for marking different lines.…”

Equilibrium properties of 3-arm star-shaped polyions: an entropic sampling Monte Carlo study

“…In this range the polymer is in a swollen state, its size is several times larger than the size of the ideal polymer. It is worth noting here that for the uncharged model of a star (with a negative interaction potential) [28,29] the dependence of R 2 g (T ) has a simple monotonic rise (Fig. 3b).…”

“…This makes achieving of equilibrium canonical distribution more difficult; evidently for star polymers the problem becomes more severe with increasing the number of arms. In previous works, we have shown that the entropic sampling Monte Carlo method [23][24][25], modified for polymer simulations [26,27], provides the possibility to investigate conformational and thermodynamic properties of neutral polymers [26], polyelectrolyte chains [27] and uncharged star-shaped polymers [28,29] in a wide temperature range.…”