Shape-Independent

Name Description Category Upload Date Author Score Verified
Guinier Porod Calculates the scattering for a generalized Guinier/power law object. This is an empirical model that can be used to determine the size and dimensionality of scattering objects, including asymmetri... Shape-Independent 15 Sep 2016 sasview 0
RPA models Calculates the macroscopic scattering intensity for a multi-component homogeneous mixture of polymers using the Random Phase Approximation. This general formalism contains 10 specific cases Case... Shape-Independent 15 Sep 2016 butler 0
star_polymer_v2 Reparametrised version, fits Rg not Rg^2^ Documentation corrected, see ticket #962, with grateful thanks to Ziang Li for pointing out the issues. The models is still noisy at very small Q when Rg... Shape-Independent 22 May 2017 richardh 0
Porod This model fits the Porod function $$ I(q) = C/q^4 $$ to the data directly without any need for linearisation (cf. Log I(q) vs Log q). Here $C = 2\pi (\Delta\rho)^2 S_v$ is the scale factor ... Shape-Independent 07 Sep 2017 sasview 0
Peak Lorentz This model describes a Lorentzian shaped peak on a flat background. Definition The scattering intensity $I(q)$ is calculated as $$ I(q) = \frac{scale}{\bigl(1+\bigl(\frac{q-q_0}{B}\big... Shape-Independent 07 Sep 2017 sasview 0
Gauss Lorentz Gel This model calculates the scattering from a gel structure, but typically a physical rather than chemical network. It is modeled as a sum of a low-q exponential decay (which happens to give a functi... Shape-Independent 07 Sep 2017 sasview 0
Broad Peak Definition This model calculates an empirical functional form for SAS data characterized by a broad scattering peak. Many SAS spectra are characterized by a broad peak even though they are fr... Shape-Independent 07 Sep 2017 sasview 0
Mass Surface Fractal A number of natural and commercial processes form high-surface area materials as a result of the vapour-phase aggregation of primary particles. Examples of such materials include soots, aerosols... Shape-Independent 07 Sep 2017 sasview 0
Rpa Definition Calculates the macroscopic scattering intensity for a multi-component homogeneous mixture of polymers using the Random Phase Approximation. This general formalism contains 10 speci... Shape-Independent 07 Sep 2017 sasview 0
Poly Gauss Coil #poly_gauss_coil model #conversion of Poly_GaussCoil.py #converted by Steve King, Mar 2016 This empirical model describes the scattering from *polydisperse* polymer chains in theta solvents or poly... Shape-Independent 07 Sep 2017 sasview 0
Polymer Excl Volume This model describes the scattering from polymer chains subject to excluded volume effects and has been used as a template for describing mass fractals. Definition The form factor was orig... Shape-Independent 07 Sep 2017 sasview 0
Mass Fractal Calculates the scattering from fractal-like aggregates based on the Mildner reference. Definition The scattering intensity $I(q)$ is calculated as $$ I(q) = scale \times P(q)S(q) + bac... Shape-Independent 07 Sep 2017 sasview 0
Be Polyelectrolyte Definition This model calculates the structure factor of a polyelectrolyte solution with the RPA expression derived by Borue and Erukhimovich. Note however that the fitting procedure here does ... Shape-Independent 07 Sep 2017 sasview 0
Spinodal Definition This model calculates the SAS signal of a phase separating solution under spinodal decomposition. The scattering intensity $I(q)$ is calculated as $$ I(q) = I_{max}\frac{(1+\gam... Shape-Independent 07 Sep 2017 sasview 0
Gel Fit *This model was implemented by an interested user!* Unlike a concentrated polymer solution, the fine-scale polymer distribution in a gel involves at least two characteristic length scales, a sho... Shape-Independent 07 Sep 2017 sasview 0
Unified Power Rg Definition This model employs the empirical multiple level unified Exponential/Power-law fit method developed by Beaucage. Four functions are included so that 1, 2, 3, or 4 levels can be used... Shape-Independent 07 Sep 2017 sasview 0
Gaussian Peak Definition This model describes a Gaussian shaped peak on a flat background $$ I(q) = (\text{scale}) \exp\left[ -\tfrac12 (q-q_0)^2 / \sigma^2 \right] + \text{background} $$ with the ... Shape-Independent 07 Sep 2017 sasview 0
Teubner Strey Definition This model calculates the scattered intensity of a two-component system using the Teubner-Strey model. Unlike `dab` this function generates a peak. A two-phase material can be char... Shape-Independent 07 Sep 2017 sasview 0
Fractal Definition This model calculates the scattering from fractal-like aggregates of spherical building blocks according the following equation: $$ I(q) = \phi\ V_\text{block} (\rho_\text{block} ... Shape-Independent 07 Sep 2017 sasview 0
Correlation Length #correlation length model # Note: model title and parameter table are inserted automatically Definition The scattering intensity I(q) is calculated as $$ I(Q) = \frac{A}{Q^n} + \frac{C}{1 ... Shape-Independent 07 Sep 2017 sasview 0
Page 1 of 2