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The full Carver and Richards 1972 2-site relaxation dispersion model for [[SQ CPMG-type data]] for most time scales. This model is labelled as '''CR72 full''' in [[Relaxation dispersion citation for relax|relax]].
== Equation ==
[http://www.nmr-relax.com/manual/Dispersion_model_summary.html Please see the summary of the model parameters here.]
* relax manual http://www.nmr-relax.com/manual/reduced_CR72_2_site_CPMG_model.html
* relaxation dispersion page of the relax website http://www.nmr-relax.com/analyses/relaxation_dispersion.html#CR72
<math>
R_{2,\textrm{eff}} = \frac{R_2^A+R_2^B+k_{\textrm{EX}}}{2} - \nu_{\textrm{cpmg}} \cosh^{-1} (D_+\cosh(\eta_+) - D_-\cos(\eta_-))
</math>
Which have the following definitions
<math>
\zeta = 2 \Delta \omega \, (R_2^A - R_2^B - p_A k_{\textrm{EX}} + p_B k_{\textrm{EX}}) \\
\Psi = (R_2^A - R_2^B - p_A k_{\textrm{EX}} + p_B k_{\textrm{EX}})^2 - \Delta \omega^2 + 4 p_A p_B k_{\textrm{ex}}^2 \\
\eta_+ = \frac{1}{\sqrt{2^3}\nu_{\textrm{cpmg}}}\sqrt{+\Psi + \sqrt{\Psi^2 + \zeta^2}} \\
\eta_- = \frac{}{\sqrt{2^3}\nu_{\textrm{cpmg}}}\sqrt{-\Psi + \sqrt{\Psi^2 + \zeta^2}} \\
D_+=\frac{1}{2}\left(1+\frac{\Psi+2\Delta \omega^2}{\sqrt{\Psi^2+z^2}} \right) \\
D_-=\frac{1}{2}\left(-1+\frac{\Psi+2\Delta \omega^2}{\sqrt{\Psi^2+z^2}} \right)
</math>
<math>k_{\textrm{EX}}</math> is the chemical exchange rate constant, <math>p_A</math> and <math>p_B</math> are the populations of states A and B, and <math>\Delta \omega</math> is the chemical shift difference between the two states in ppm.
== Parameters ==