2017/10/30 by H. Meyer, Meyer, Hendrik, Eric Horwath +3
Biochemistry, Genetics and Molecular Biology · Physics and Astronomy · #Advanced Thermodynamics and Statistical Mechanics #FOS: Physical sciences #Force Microscopy Techniques and Applications #Protein Structure and Dynamics #Soft Condensed Matter (cond-mat.soft)
paper · pdf · doi:10.48550/arxiv.1710.11077
openalex publication_date 2017/10/30 · openalex created_date 2025/10/10 · openalex updated_date 2026/07/28
In polymer physics it is typically assumed that excluded volume interactions\nare effectively screened in polymer melts. Hence, chains could be described by\nan effective random walk without excluded volume interactions. In this letter,\nwe show that this mapping is problematic by analyzing the occurrence of knots,\ntheir spectrum and sizes in polymer melts, corresponding random walks and\nchains in dilute solution. The effective random walk severely overrates the\noccurrence of knots and their complexity, particularly when compared to melts\nof flexible chains, indicating that non-trivial effects due to remnants of\nself-avoidance still play a significant role for the chain lengths considered\nin this numerical study. For melts of semiflexible chains, the effect is less\npronounced. In addition, we find that chains in a melt are very similar in\nstructure and topology to dilute single chains close to the collapse\ntransition, which indicates that the latter are also not well-represented by\nrandom walks. We finally show that typical equilibration procedures are\nwell-suited to relax the topology in melts.\n