Account:

Line This model calculates intensity using simple linear function Definition The scattering intensity $I(q)$ is calculated as $$I(q) = \text{scale} (A + B \cdot q) + \text{background}$$ .. note:: For 2D plots intensity has different...
Parallelepiped # parallelepiped model # Note: model title and parameter table are inserted automatically Definition This model calculates the scattering from a rectangular solid (parallelepiped-image). If you need to apply polydispersity, see also recta...
Guinier Definition This model fits the Guinier function $$I(q) = \text{scale} \cdot \exp{\left[ \frac{-Q^2 R_g^2 }{3} \right]} + \text{background}$$ to the data directly without any need for linearisation (*cf*. the usual plot of $\ln I(q)$ v...
Two Power Law Definition The scattering intensity $I(q)$ is calculated as $$I(q) = \begin{cases} A q^{-m1} + \text{background} & q <= q_c \\ C q^{-m2} + \text{background} & q > q_c \end{cases}$$ where $q_c$ = the location of the crossover from one ...
Pringle Definition The form factor for this bent disc is essentially that of a hyperbolic paraboloid and calculated as $$P(q) = (\Delta \rho )^2 V \int^{\pi/2}_0 d\psi \sin{\psi} sinc^2 \left( \frac{qd\cos{\psi}}{2} \right) \left[ \left( S^2_0+... Linear Pearls This model provides the form factor for N spherical pearls of radius R linearly joined by short strings (or segment length or edge separation) l (= A - 2R). A is the center-to-center pearl separation distance. The thickness of each strin... Polymer Micelle This model provides the form factor, P(q), for a micelle with a spherical core and Gaussian polymer chains attached to the surface, thus may be applied to block copolymer micelles. To work well the Gaussian chains must be much smaller than th... Lorentz Lorentz (Ornstein-Zernicke Model) Definition The Ornstein-Zernicke model is defined by$$ I(q)=\frac{\text{scale}}{1+(qL)^2}+\text{background} $$The parameter L is the screening length *cor_length*. For 2D data the scattering in... Fcc Paracrystal #fcc paracrystal model #note model title and parameter table are automatically inserted #note - calculation requires double precision .. warning:: This model and this model description are under review following concerns raised by Sa... Raspberry Definition The figure below shows a schematic of a large droplet surrounded by several smaller particles forming a structure similar to that of Pickering emulsions. Schematic of the raspberry model In order to calculate the form... Onion This model provides the form factor, P(q), for a multi-shell sphere where the scattering length density (SLD) of each shell is described by an exponential, linear, or constant function. The form factor is normalized by the volume of the sphere w... Power Law #power_law model #conversion of PowerLawAbsModel.py #converted by Steve King, Dec 2015 This model calculates a simple power law with a flat background. Definition$$ I(q) = \text{scale} \cdot q^{-\text{power}} + \text{background}  ...