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
\[q=\sqrt{q_x^2 + q_y^2}\]
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Fig. 93 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.