Water sLED pl.c (Pascale Legault)

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Basic facts about water_sLED_pl

Synopsis: measures diffusion of biomolecules in water

Family: Diffusion experiments

Code authors:

Pascale Legault

Copyright: P. Legault, lab webpage, University of Montreal

Amplitude of the echo follows the equation:

$A = A_0 e^{-(\gamma \delta G)^2(\Delta-\frac{\delta}{3})D_s}$

Parameters translate in the following way (bold are vnmr parameters, units are in parentheses):

Fit the data to a simple equation:

$y = a e^{-b x^2}$

It's a Gaussian curve with center at 0, where x = gzlvl2, y = peak intensity.

Then extract $D s$ from b:

$\textstyle D_s = \frac{b}{{(gt2 \cdot \gamma \cdot G_{gzlvl2=1})}^2(gdelta-gt2/3)}$

Above, G(gzlvl2=1) is a probe-specific value of field gradient in Gauss per unit gzlvl2.