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Updated: Aug 1, 2026
07:55
Flexural Rigidity Measurements of Biopolymers Using Gliding Assays
Published on: November 9, 2012
End-to-end distribution function of stiff polymers for all persistence lengths
1Institut fr Theoretische Physik, Freie Universitt Berlin, Germany. bodo.hamprecht@physik.fu-berlin.de
Summary
We derived a new analytic expression for wormlike chain end-to-end distributions in 3D. This formula accurately models chains across all stiffnesses, from flexible to stiff, matching simulation data.
Area of Science:
- Polymer Physics
- Statistical Mechanics
Background:
- The Porod-Kratky wormlike chain model is crucial for describing semiflexible polymers.
- Calculating the end-to-end distance distribution is essential for understanding polymer conformation.
Purpose of the Study:
- To develop a general analytical method for computing polymer chain properties.
- To derive a precise end-to-end distance distribution for wormlike chains.
Main Methods:
- Established recursion relations for calculating even moments of the end-to-end distance.
- Derived an analytical expression for the end-to-end distribution in D dimensions.
Main Results:
- Developed a simple, all-encompassing analytical expression for the 3D end-to-end distribution.
- Demonstrated excellent agreement with Monte Carlo simulations for stiff chains.
- Showed the distribution converges to Gaussian random-walk behavior for low stiffness.
Conclusions:
- The derived analytical expression provides a unified description of wormlike chain behavior.
- This method offers a computationally efficient alternative to simulations for certain polymer properties.
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