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Posted by tlinnet on May 06, 2014 - 17:35:
Author: tlinnet
Date: Tue May  6 17:35:00 2014
New Revision: 23025

URL: http://svn.gna.org/viewcvs/relax?rev=23025&view=rev
Log:
Added model B14 description in the manual.

sr #3154: (https://gna.org/support/?3154) Implementation of Baldwin (2014) 
B14 model - 2-site exact solution model for all time scales.

This follows the tutorial for adding relaxation dispersion models at:
http://wiki.nmr-relax.com/Tutorial_for_adding_relaxation_dispersion_models_to_relax#The_relax_manual


Modified:
    trunk/docs/latex/dispersion.tex

Modified: trunk/docs/latex/dispersion.tex
URL: 
http://svn.gna.org/viewcvs/relax/trunk/docs/latex/dispersion.tex?rev=23025&r1=23024&r2=23025&view=diff
==============================================================================
--- trunk/docs/latex/dispersion.tex     (original)
+++ trunk/docs/latex/dispersion.tex     Tue May  6 17:35:00 2014
@@ -102,6 +102,11 @@
     $2*\taucpmg$ is the time between successive 180 degree pulses.
     Parameters are $\{\RtwozeroA, \dots, \dw, \kAB\}$.
     See Section~\ref{sect: dispersion: TSMFK01 model} on page~\pageref{sect: 
dispersion: TSMFK01 model}.
+  \item[`B14':]\index{relaxation dispersion!B14 model}  The reduced 
\citet{Baldwin2014} 2-site exact solution equation for all time scales 
whereby the simplification $\RtwozeroA = \RtwozeroB$ is assumed.
+    It has the parameters $\{\Rtwozero, \dots, \pA, \dw, \kex\}$.
+    See Section~\ref{sect: dispersion: B14 model} on page~\pageref{sect: 
dispersion: B14 model}.
+  \item[`B14 full':]\index{relaxation dispersion!B14 full model}  The full 
\citet{Baldwin2014} 2-site exact equation for all time scales with parameters 
$\{\RtwozeroA, \RtwozeroB, \dots, \pA, \dw, \kex\}$.
+    See Section~\ref{sect: dispersion: B14 full model} on 
page~\pageref{sect: dispersion: B14 full model}.
 \end{description}
 
 For the SQ CPMG-type experiments, the numeric models currently supported are:
@@ -549,6 +554,78 @@
   \item the relaxation dispersion page of the relax website at 
\url{http://www.nmr-relax.com/analyses/relaxation\_dispersion.html#TSMFK01}.
 \end{itemize}
 
+
+% Full B14 model.
+%~~~~~~~~~~~~~~~~~
+
+\subsection{The full B14 2-site CPMG model}
+\label{sect: dispersion: B14 full model}
+\index{relaxation dispersion!B14 full model|textbf}
+
+This is the model for 2-site exchange exact analytical derivation on all 
time scales (with the constraint that $\pA > \pB$), named after 
\citet{Baldwin2014}.
+It is selected by setting the model to `B14 full'.
+The equation is
+\begin{equation}
+    R_{2,\textrm{eff}} = 
\frac{R_2^A+R_2^B+k_{\textrm{EX}}}{2}-\frac{N_{\textrm{CYC}}}{T_{\textrm{rel}}}\cosh{}^{-1}(v_{1c})
 - \frac{1}{T_{\textrm{rel}}}\ln{\left( \frac{1+y}{2} + 
\frac{1-y}{2\sqrt{v_{1c}^2-1}}(v_2 + 2k_{\textrm{AB}}p_D )\right)} \\
+    = R_{2,\textrm{eff}}^{\textrm{CR72}} - 
\frac{1}{T_{\textrm{rel}}}\ln{\left( \frac{1+y}{2} + 
\frac{1-y}{2\sqrt{v_{1c}^2-1}}(v_2 + 2k_{\textrm{AB}}p_D )\right)} ,
+\end{equation}
+
+where
+\begin{equation}
+    v_{1c} = 
F_0\cosh{\left(\tau_{\textrm{CP}}E_0\right)}-F_2\cosh{\left(\tau_{\textrm{CP}}E_2\right)}
 \\
+    v_{1s} = 
F_0\sinh{\left(\tau_{\textrm{CP}}E_0\right)}-F_2\sinh{\left(\tau_{\textrm{CP}}E_2\right)}
 \\
+    v_{2}N = v_{1s}\left(O_B-O_A\right)+4O_B F_1^a 
\sinh{\left(\tau_{\textrm{CP}}E_1\right)} \\
+    p_D N = v_{1s} + 
\left(F_1^a+F_1^b\right)\sinh{\left(\tau_{\textrm{CP}}E_1\right)}\\
+    v_3 = \left( v_2^2 + 4 k_{\textrm{BA}} k_{\textrm{AB}} p_D^2 
\right)^{1/2} \\
+    y = \left( \frac{v_{1c}-v_3}{v_{1c}+v_3} \right)^{N_{\textrm{CYC}}}
+\end{equation}
+
+The advantage of this code will be that you will always get the right answer 
provided you got 2-site exchange, in-phase magnetisation and on-resonance 
pulses. 
+
+The term $$p_D$$ is based on product of the off diagonal elements in the 
CPMG propagator (Supplementary Section 3, \citet{Baldwin2014}).
+
+It is interesting to consider the region of validity of the Carver Richards 
result. The two results are equal when the correction is zero, which is true 
when
+
+\begin{equation}
+    \sqrt{v_{1c}^2-1} \approx v_2 + 2k_{\textrm{AB}}p_D
+\end{equation}
+
+This occurs when $$k_{\textrm{AB}}p_D$$ tends to zero, and so $$v_2=v_3$$.
+Setting $$k_{\textrm{AB}}p_D$$ to zero, amounts to neglecting magnetisation 
that starts on the ground state ensemble and end on the excited state 
ensemble and vice versa. 
+This will be a good approximation when $$p_A \gg p_B$$.
+In practise, significant deviations from the Carver Richards equation can be 
incurred if $$p_B > 1\%$$.
+Incorporation of the correction term, results in an improved description of 
the CPMG experiment over the Carver Richards equation 
\citet{CarverRichards72}.
+
+The reference for this equation is:
+\begin{itemize}
+  \item \bibentry{Baldwin2014}
+\end{itemize}
+
+More information about the B14 full model is available from:
+\begin{itemize}
+  \item the relax wiki at \url{http://wiki.nmr-relax.com/B14\_full},
+  \item the API documentation at 
\url{http://www.nmr-relax.com/api/3.1/lib.dispersion.B14-module.html},
+  \item the relaxation dispersion page of the relax website at 
\url{http://www.nmr-relax.com/analyses/relaxation\_dispersion.html#B14\_full}.
+\end{itemize}
+
+
+% B14 model.
+%~~~~~~~~~~~~
+
+\subsection{The reduced B14 2-site CPMG model}
+\label{sect: dispersion: B14 model}
+\index{relaxation dispersion!B14 model|textbf}
+
+This is the model for 2-site exchange exact analytical derivation on all 
time scales (with the constraint that $\pA > \pB$), named after 
\citet{Baldwin2014}.
+It is selected by setting the model to `B14'.
+It is the same as the full B14 model described above, but with the 
simplification that $\RtwozeroA = \RtwozeroB$.
+
+More information about the B14 model is available from:
+\begin{itemize}
+  \item the relax wiki at \url{http://wiki.nmr-relax.com/B14},
+  \item the API documentation at 
\url{http://www.nmr-relax.com/api/3.1/lib.dispersion.B14-module.html},
+  \item the relaxation dispersion page of the relax website at 
\url{http://www.nmr-relax.com/analyses/relaxation\_dispersion.html#B14}.
+\end{itemize}
 
 
 % The numeric CPMG models.




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