Computer simulations of n-alkane melts

Abstract

Stochastic dynamics simulations of n‐alkane melts (C₁₃H₂₈ and C₂₈H₅₈ ) have been performed in order to calculate their static properties. The system consists of linear chains of mass points, which are connected by fixed bond lengths. Each point of a chain is subjected to valence bond and torsional forces. Additionally, nonbonded interactions are taken into account by a truncated, Lennard‐Jones potential. The mean‐square end‐to‐end distance and the radius of gyration of the chains as well as the average fraction of trans conformations were calculated and compared with the results obtained by Monte Carlo simulations and by unperturbed rotational isomeric states model calculations. The comparison exhibits very good agreement between the results of the different approaches, and demonstrates the potential advantages of stochastic dynamics simulations for polymeric systems. An investigation of different torsional potentials exhibited the subtle effect of the curvature of the torsional potential on bulk structures.