Author: bugman Date: Wed Oct 16 15:19:17 2013 New Revision: 21139 URL: http://svn.gna.org/viewcvs/relax?rev=21139&view=rev Log: Improvements for the LaTeX maths commands used in the dispersion chapter of the user manual. Modified: branches/relax_disp/docs/latex/dispersion.tex branches/relax_disp/docs/latex/relax.tex Modified: branches/relax_disp/docs/latex/dispersion.tex URL: http://svn.gna.org/viewcvs/relax/branches/relax_disp/docs/latex/dispersion.tex?rev=21139&r1=21138&r2=21139&view=diff ============================================================================== --- branches/relax_disp/docs/latex/dispersion.tex (original) +++ branches/relax_disp/docs/latex/dispersion.tex Wed Oct 16 15:19:17 2013 @@ -159,22 +159,22 @@ For the fixed relaxation time period CPMG-type experiments, the $\Rtwoeff$/$\Ronerho$ values are determined by direct calculation using the formula \begin{equation} - R_{2\textrm{eff}}(\nucpmg) = - \frac{1}{T_\textrm{relax}} \cdot \ln \left( \frac{I_1(\nucpmg)}{I_0} \right) . + \Rtwoeff(\nucpmg) = - \frac{1}{T_\textrm{relax}} \cdot \ln \left( \frac{I_1(\nucpmg)}{I_0} \right) . \end{equation} The values and errors are determined with a single call of the \uf{calc} user function. The $\Ronerho$ version of the equation is essentially the same: \begin{equation} - R_{1\rho}(\omega_1) = - \frac{1}{T_\textrm{relax}} \cdot \ln \left( \frac{I_1(\omega_1)}{I_0} \right) . + \Ronerho(\omega_1) = - \frac{1}{T_\textrm{relax}} \cdot \ln \left( \frac{I_1(\omega_1)}{I_0} \right) . \end{equation} Errors are calculated using the formula \begin{equation} \label{eq: dispersion error} - \sigma_{\textrm{R}_2} = \frac{1}{T_\textrm{relax}} \sqrt{ \left( \frac{\sigma_{I_1}}{I_1(\omega_1)} \right)^2 + \left( \frac{\sigma_{I_0}}{I_0} \right)^2 } . + \sigma_{\Rtwo} = \frac{1}{T_\textrm{relax}} \sqrt{ \left( \frac{\sigma_{I_1}}{I_1(\omega_1)} \right)^2 + \left( \frac{\sigma_{I_0}}{I_0} \right)^2 } . \end{equation} In a number of publications, the error formula from \citet{IshimaTorchia05} has been used. This is the collapse of Equation~\ref{eq: dispersion error} by setting $\sigma_{I_0}$ to zero: \begin{equation} \label{eq: IT05 dispersion error} - \sigma_{\textrm{R}_2} = \frac{\sigma_{I_1}}{T_\textrm{relax} I_1(\omega_1)} . + \sigma_{\Rtwo} = \frac{\sigma_{I_1}}{T_\textrm{relax} I_1(\omega_1)} . \end{equation} This is not implemented in relax as it can be shown by simple simulation that the formula is incorrect (see Figure~\ref{fig: dispersion error comparison}). This formula significantly underestimates the real errors. The use of the same $I_0$ value for all dispersion points does not cause a decrease in the $\Rtwoeff$ error but rather a correlation in the errors. @@ -228,7 +228,7 @@ or rearranged as: \begin{equation} \label{eq: Luz-Meiboom} - \Rex = \sum_{i=2}^n \frac{\Phi_\textrm{ex,i}}{\textrm{k}_\textrm{i}} \cdot \left( 1 - \frac{4\nucpmg}{\textrm{k}_\textrm{i}} \cdot \tanh \left( \frac{\textrm{k}_\textrm{i}}{4\nucpmg} \right) \right) , + \Rex = \sum_{i=2}^n \frac{\Phiexi}{\textrm{k}_\textrm{i}} \cdot \left( 1 - \frac{4\nucpmg}{\textrm{k}_\textrm{i}} \cdot \tanh \left( \frac{\textrm{k}_\textrm{i}}{4\nucpmg} \right) \right) , \end{equation} @@ -254,7 +254,7 @@ It is selected by setting the model to `LM63 3-site'. Taking the original Equation~\ref{eq: Luz-Meiboom}, the equation for 3-site exchange is simply: \begin{equation} - \Rex = \sum_{i=2}^3 \frac{\Phi_\textrm{ex,i}}{\textrm{k}_\textrm{i}} \cdot \left( 1 - \frac{4\nucpmg}{\textrm{k}_\textrm{i}} \cdot \tanh \left( \frac{\textrm{k}_\textrm{i}}{4\nucpmg} \right) \right) , + \Rex = \sum_{i=2}^3 \frac{\Phiexi}{\textrm{k}_\textrm{i}} \cdot \left( 1 - \frac{4\nucpmg}{\textrm{k}_\textrm{i}} \cdot \tanh \left( \frac{\textrm{k}_\textrm{i}}{4\nucpmg} \right) \right) , \end{equation} The reference for this equation is: @@ -307,15 +307,15 @@ It is selected by setting the model to `CR72 full'. The equation is \begin{equation} - \Rtwoeff = \frac{1}{2} \Big( \textrm{R}_\textrm{2A}^0 + \textrm{R}_\textrm{2B}^0 + \kex - 2\nucpmg\cosh^{-1} \big( D_+\cosh(\eta_+) - D_-\cos(\eta_-) \big) \Big) , + \Rtwoeff = \frac{1}{2} \Big( \RtwozeroA + \RtwozeroB + \kex - 2\nucpmg\cosh^{-1} \big( D_+\cosh(\eta_+) - D_-\cos(\eta_-) \big) \Big) , \end{equation} where \begin{align} D_\pm &= \frac{1}{2} \left( \pm1 + \frac{\Psi + 2\dw^2}{\sqrt{\Psi^2 + \zeta^2}} \right) , \\ \eta_\pm &= 2^{\frac{2}{3}}\frac{1}{\nucpmg} \left( \pm\Psi + \sqrt{\Psi^2 + \zeta^2} \right)^{\frac{1}{2}} , \\ - \Psi &= \left( \textrm{R}_\textrm{2A}^0 - \textrm{R}_\textrm{2B}^0 - \pA\kex + \pB\kex \right)^2 - \dw^2 + 4\pA\pB\kex^2 , \\ - \zeta &= 2\dw \left( \textrm{R}_\textrm{2A}^0 - \textrm{R}_\textrm{2B}^0 - \pA\kex + \pB\kex \right). + \Psi &= \left( \RtwozeroA - \RtwozeroB - \pA\kex + \pB\kex \right)^2 - \dw^2 + 4\pA\pB\kex^2 , \\ + \zeta &= 2\dw \left( \RtwozeroA - \RtwozeroB - \pA\kex + \pB\kex \right). \end{align} The reference for this equation is: Modified: branches/relax_disp/docs/latex/relax.tex URL: http://svn.gna.org/viewcvs/relax/branches/relax_disp/docs/latex/relax.tex?rev=21139&r1=21138&r2=21139&view=diff ============================================================================== --- branches/relax_disp/docs/latex/relax.tex (original) +++ branches/relax_disp/docs/latex/relax.tex Wed Oct 16 15:19:17 2013 @@ -158,17 +158,19 @@ \newcommand{\Phiex}{\Phi_\textrm{ex}} \newcommand{\PhiexB}{\Phi_\textrm{ex,B}} \newcommand{\PhiexC}{\Phi_\textrm{ex,C}} +\newcommand{\Phiexi}{\Phi_\textrm{ex,i}} \newcommand{\Rex}{\mathrm{R}_\textrm{ex}} \newcommand{\Ronerhoprime}{\mathrm{R}_{1\rho}'} -\newcommand{\Rtwoeff}{\mathrm{R}_{2\textrm{eff}}} +\newcommand{\Rtwoeff}{\mathrm{R}_\textrm{2eff}} \newcommand{\Rtwozero}{\mathrm{R}_2^0} -\newcommand{\RtwozeroA}{\mathrm{R}_{2A}^0} -\newcommand{\RtwozeroB}{\mathrm{R}_{2B}^0} -\newcommand{\RtwozeroC}{\mathrm{R}_{2C}^0} -\newcommand{\RtwoDQA}{\mathrm{R}_{2,DQ}^A} -\newcommand{\RtwoDQB}{\mathrm{R}_{2,DQ}^B} -\newcommand{\RtwoZQA}{\mathrm{R}_{2,ZQ}^A} -\newcommand{\RtwoZQB}{\mathrm{R}_{2,ZQ}^B} +\newcommand{\RtwozeroA}{\mathrm{R}_\mathrm{2A}^0} +\newcommand{\RtwozeroB}{\mathrm{R}_\mathrm{2B}^0} +\newcommand{\RtwozeroC}{\mathrm{R}_\mathrm{2C}^0} +\newcommand{\RtwozeroMQ}{\mathrm{R}_\mathrm{2,MQ}^0} +\newcommand{\RtwoDQA}{\mathrm{R}_\mathrm{2,DQ}^\mathrm{A}} +\newcommand{\RtwoDQB}{\mathrm{R}_\mathrm{2,DQ}^\mathrm{B}} +\newcommand{\RtwoZQA}{\mathrm{R}_\mathrm{2,ZQ}^\mathrm{A}} +\newcommand{\RtwoZQB}{\mathrm{R}_\mathrm{2,ZQ}^\mathrm{B}} \newcommand{\tex}{\tau_\textrm{ex}} \newcommand{\taucpmg}{\tau_\textrm{CPMG}}