Models the Q dependence of the QENS line width (Gamma (hwhm)), diffusion coefficients (D), residence times (tau) and jump lengths (l) to extract the associated long range diffusive motions of molecules.
The Hall-Ross Jump diffusion model [1] has the form:
Units of l are inverse units of Q.
Units of Gamma are meV if units of τ are ps. Alternatively, units of Gamma are \mu`eV if units of :math:tau` are ns.
Mean square diffusion jump length = 3 l^2 \ \AA^2.
Diffusion coefficient D = \frac{l^2}{2 \tau} \ \AA^2 ps^{-1}.
Name | Default | Description |
---|---|---|
Tau | 1.0 | Residence time |
L | 0.2 | Standard deviation of jump lengths |
[1] |
|
Categories: FitFunctions | QuasiElastic
Python: HallRoss.py