Elastic traits of the extensible discrete wormlike chain model

Polymer models play the special role of elucidating the elementary features describing the physics of long molecules and become essential to interpret the measurements of their magnitudes. In this work the end-to-end distance of an extensible discrete wormlike chain polymer as a function of the applied force has been calculated both numerically and analytically, the latter as an effective approximation. The numerical evaluation uses the transfer matrix formalism to obtain an exact calculation of the partition function, while the analytic derivations generalize the simple phenomenological formulas largely used up to now. The obtained formulas are simple enough to be implemented in the fit analysis of experimental data of semiflexible extensible polymers, with the result that the elastic parameters obtained are compatible with previous measurements, and more, their accuracy strongly improves in a large range of chain extensibility.

Automated summary

In this study, the relationship between the end-to-end distance and the applied force of an extensible discrete wormlike chain polymer was calculated using both numerical and analytical methods. The numerical approach used the transfer matrix formalism to obtain an exact calculation of the partition function, while the analytical derivations generalized the simple phenomenological formulas commonly used. The obtained formulas are simple enough to be applied in fitting experimental data, and the results showed that the elastic parameters obtained are consistent with previous measurements and have significantly improved accuracy in a wide range of chain extensibility.