| Capped Cylinder |
Definitions
Calculates the scattering from a cylinder with spherical section end-caps. Like `barbell`, this is a sphereocylinder with end caps that have a radius larger than that of the cylinder, but with the center of the end cap radius lying… |
| Fractal |
Definition
This model calculates the scattering from fractal-like aggregates of spherical building blocks according the following equation:
$$ I(q) = \phi\ V_\text{block} (\rho_\text{block} - \rho_\text{solvent})^2 P(q)S(q) + \text{background… |
| Sphere |
For information about polarised and magnetic scattering, see the `magnetism` documentation.
Definition
The 1D scattering intensity is calculated in the following way (Guinier, 1955)
$$ I(q) = \frac{\text{scale}}{V} \cdot \left[ 3V(\Delt… |
| Teubner Strey |
Definition
This model calculates the scattered intensity of a two-component system using the Teubner-Strey model. Unlike `dab` this function generates a peak. A two-phase material can be characterised by two length scales - a correlation lengt… |
| Hollow Rectangular Prism |
# rectangular_prism model # Note: model title and parameter table are inserted automatically Definition
This model provides the form factor, $P(q)$, for a hollow rectangular parallelepiped with a wall of thickness $\Delta$. The 1D scattering i… |
| Lamellar Hg |
# Note: model title and parameter table are inserted automatically This model provides the scattering intensity, $I(q)$, for a lyotropic lamellar phase where a random distribution in solution are assumed. The SLD of the head region is taken to be di… |
| Rectangular Prism |
# rectangular_prism model # Note: model title and parameter table are inserted automatically
This model provides the form factor, $P(q)$, for a rectangular prism.
Note that this model is almost totally equivalent to the existing `parallelepipe… |
| Hollow Cylinder |
Definition
This model provides the form factor, $P(q)$, for a monodisperse hollow right angle circular cylinder (rigid tube) where the The inside and outside of the hollow cylinder are assumed to have the same SLD and the form factor is thus n… |
| Barbell |
Definition
Calculates the scattering from a barbell-shaped cylinder. Like `capped-cylinder`, this is a spherocylinder with spherical end caps that have a radius larger than that of the cylinder, but with the center of the end cap radius lying… |
| Lamellar Stack Paracrystal |
# Note: model title and parameter table are inserted automatically This model calculates the scattering from a stack of repeating lamellar structures. The stacks of lamellae (infinite in lateral dimension) are treated as a paracrystal to account for… |
| Gaussian Peak |
Definition
This model describes a Gaussian shaped peak on a flat background
$$ I(q) = (\text{scale}) \exp\left[ -\tfrac12 (q-q_0)^2 / \sigma^2 \right] + \text{background}
$$
with the peak having height of *scale* centered at $q_0$ and … |
| Unified Power Rg |
Definition
This model employs the empirical multiple level unified Exponential/Power-law fit method developed by Beaucage. Four functions are included so that 1, 2, 3, or 4 levels can be used. In addition a 0 level has been added which simply … |
| Lamellar Hg Stack Caille |
# Note: model title and parameter table are inserted automatically This model provides the scattering intensity, $I(q) = P(q)S(q)$, for a lamellar phase where a random distribution in solution are assumed. Here a Caille $S(q)$ is used for the lamell… |
| Spinodal |
Definition
This model calculates the SAS signal of a phase separating system undergoing spinodal decomposition. The scattering intensity $I(q)$ is calculated as
$$ I(q) = I_{max}\frac{(1+\gamma/2)x^2}{\gamma/2+x^{2+\gamma}}+B
$$
where $x=q… |
| Ellipsoid |
# ellipsoid model # Note: model title and parameter table are inserted automatically The form factor is normalized by the particle volume
Definition
The output of the 2D scattering intensity function for oriented ellipsoids is given by (Fei… |