| 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… |
| Pearl Necklace |
This model provides the form factor for a pearl necklace composed of two elements: *N* pearls (homogeneous spheres of radius *R*) freely jointed by *M* rods (like strings - with a total mass *Mw* = *M* \* *m*`r` + *N* \* *m*\ `s`, and the string seg… |
| Sc Paracrystal |
Definition
Calculates the scattering from a **simple cubic lattice** with paracrystalline distortion. Thermal vibrations are considered to be negligible, and the size of the paracrystal is infinitely large. Paracrystalline distortion is assume… |
| Lamellar |
Polydispersity in the bilayer thickness can be applied from the GUI.
Definition
The scattering intensity $I(q)$ for dilute, randomly oriented, "infinitely large" sheets or lamellae is
$$ I(q) = \text{scale}\frac{2\pi P(q)}{q^2\delta} + … |
| Polymer Excl Volume |
This model describes the scattering from polymer chains subject to excluded volume effects and has been used as a template for describing mass fractals.
Definition
The form factor was originally presented in the following integral form (Ben… |
| Mass Fractal |
Calculates the scattering from fractal-like aggregates based on the Mildner reference.
Definition
The scattering intensity $I(q)$ is calculated as
$$ I(q) = scale \times P(q)S(q) + background
$$
$$ P(q) = F(qR)^2
$$
$$ F(x) = \frac{… |
| Flexible Cylinder |
This model provides the form factor, $P(q)$, for a flexible cylinder where the form factor is normalized by the volume of the cylinder. **Inter-cylinder interactions are NOT provided for.**
$$ P(q) = \text{scale} \left<F^2\right>/V + \text{backg… |