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Origin of metastable knots in single flexible chains
Liang Dai1, C Benjamin Renner2, Patrick S Doyle3
1BioSystems and Micromechanics IRG, Singapore-MIT Alliance for Research and Technology Centre, Singapore 117543, Singapore.
Physical Review Letters
|February 7, 2015
Summary
We developed a new theory explaining knot size distribution and metastable knots in flexible polymers. This research bridges a gap in polymer physics, offering insights into macroscopic knot phenomena.
Area of Science:
- Polymer Physics
- Theoretical Chemistry
Background:
- Knotting of semiflexible polymers is well-understood theoretically.
- Knotting of flexible polymers remains a relatively unexplored area in polymer physics.
Purpose of the Study:
- To develop a new theory for the size distribution of knots on flexible polymers.
- To investigate the existence and characteristics of metastable knots in flexible polymer systems.
Main Methods:
- Mapping the free energy of a flexible molecule in a tube to the free energy distribution of a knot on a flexible chain.
- Theoretical modeling and analysis of polymer knotting phenomena.
Main Results:
- A novel theory for the size distribution of knots on flexible polymers has been established.
- The existence of metastable knots in flexible polymer systems is theoretically supported.
- The free energy distribution of knots on flexible chains can be quantitatively reproduced by mapping.
Conclusions:
- The developed theory provides a framework for understanding flexible polymer knotting.
- The size distribution of knots on flexible chains is predicted to be universal.
- These findings may have observable consequences at macroscopic scales, such as with a string of hard balls.
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