helixmc.fitfxn.wlc_odijk

helixmc.fitfxn.wlc_odijk(F, A, L, S, kT=41.164043971999995)

Worm-like chain fitting formula described in Odijk 1995 paper. It is an extensive WLC model.

Parameters:

F : float or 1D ndarray

Z-direction stretching force, in pN.

A : float

Bending persistence length, in Å.

L : float

Contour length, in Å.

S : float

Stretch modulus, in pN.

kT : float, optional

Temperature times Boltzmann constant, in pN.Å. Default is 298.15 K.

Returns:

z : float or 1D ndarray

Average Z-extension of the helix, in Å.

Notes

The fitting function [1] is

\[z = L \left( 1 - \frac{1}{2} \sqrt{ \frac{k T} {F A} } + \frac{F}{S} \right)\]

References

[1]	Odijk, T. (1995) Stiff Chains and Filaments under Tension. Macromolecules 28: 7016-7018.