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Statistical mechanics of helical wormlike chain model
1Department of Physics, Lehigh University, Bethlehem, Pennsylvania 18015, USA. yal209@lehigh.edu
The Journal of Chemical Physics
|February 17, 2011
Summary
We explored polymer mechanics using the helical wormlike model, finding no Lifshitz point between disordered and helical phases. Our numerical and theoretical analysis offers insights into chiral polymer statics, including dsDNA.
Area of Science:
- Statistical mechanics
- Polymer physics
- Soft matter physics
Background:
- The helical wormlike model describes polymers with bending and torsional elasticity.
- Understanding the phase behavior of such polymers is crucial for various applications.
Purpose of the Study:
- To numerically solve the helical wormlike model using a transfer matrix formulation.
- To investigate the statistical mechanics and phase behavior of polymers with bending and torsional elasticity.
Main Methods:
- Factorizable energy function enabling a transfer matrix formulation.
- Numerical calculation of tangent-tangent and binormal-binormal correlation functions.
- Theoretical analysis of asymptotic behavior at low temperatures.
Main Results:
- Calculated correlation functions show rich profiles dependent on temperature and equilibrium torsion.
- Evidence suggests no finite-temperature Lifshitz point exists between disordered and helical phases.
- Theoretical predictions for low-temperature asymptotic behavior align well with numerical results.
Conclusions:
- The helical wormlike model exhibits complex behavior influenced by temperature and torsion.
- Absence of a finite-temperature Lifshitz point clarifies phase transitions in chiral polymers.
- The developed analysis framework is applicable to understanding the statics of double-stranded DNA (dsDNA) and other chiral polymers.
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