lorentz

Ornstein-Zernicke correlation length model

Parameter Description Units Default value
scale Source intensity None 1
background Source background cm-1 0.001
cor_length Screening length Å 50

The returned value is scaled to units of cm-1 sr-1, absolute scale.

Lorentz (Ornstein-Zernicke Model)

Definition

The Ornstein-Zernicke model is defined by

\[I(q)=\frac{\text{scale}}{1+(qL)^2}+\text{background}\]

The parameter \(L\) is the screening length cor_length.

For 2D data the scattering intensity is calculated in the same way as 1D, where the \(q\) vector is defined as

\[q=\sqrt{q_x^2 + q_y^2}\]
../../_images/lorentz_autogenfig.png

Fig. 106 1D plot corresponding to the default parameters of the model.

References

L.S. Qrnstein and F. Zernike, Proc. Acad. Sci. Amsterdam 17, 793 (1914), and Z. Phys. 19, 134 (1918), and 27, 761 {1926); referred to as QZ.