Related Experiment Video
Updated: Jul 5, 2026

Magnetic Tweezers for the Measurement of Twist and Torque
Published on: May 19, 2014
Tightness of random knotting
V Katritch1, W K Olson, A Vologodskii
1Department of Chemistry, Rutgers, State University of New Jersey, New Brunswick 08903, USA.
Abstract:
Long polymers in solution frequently adopt knotted configurations. To understand the physical properties of knotted polymers, it is important to find out whether the knots formed at thermodynamic equilibrium are spread over the whole polymer chain or rather are localized as tight knots. We present here a method to analyze the knottedness of short linear portions of simulated random chains. Using this method, we observe that knot-determining domains are usually very tight, so that, for example, the preferred size of the trefoil-determining portions of knotted polymer chains corresponds to just seven freely jointed segments.
Related Concept Videos
Spin–Spin Coupling: Three-Bond Coupling (Vicinal Coupling)
The extent of coupling depends on the C‑C bond length, the two H‑C‑C angles, any electron-withdrawing substituents, and the dihedral angle between the involved orbitals. The...
Relation between Poisson's ratio, Modulus of Elasticity and Modulus of Rigidity
Angle of Twist - Elastic Range
Torsion of Noncircular Members
Stability of structures
Torsion in Vector Calculus

