NS CPMG 2-site 3D full

The relaxation dispersion model for the numeric solution (NS) to the Bloch-McConnell equations for SQ CPMG-type data using 3D magnetisation vectors. The model is labelled as NS CPMG 2-site 3D full in relax.

Parameters

The NS CPMG 2-site 3D full model has the parameters {R_2A⁰, R_2B⁰, ..., p_A, Δω, k_ex}.

Code

The library code: https://sourceforge.net/p/nmr-relax/code/ci/master/tree/lib/dispersion/ns_cpmg_2site_3d.py

References

The function uses an explicit matrix that contains relaxation, exchange and chemical shift terms. It does the 180deg pulses in the CPMG train. The approach of Bloch-McConnell can be found in chapter 3.1 of Palmer, A. G. Chem Rev 2004, 104, 3623-3640. This function was written, initially in MATLAB, in 2010.

This is the model of the numerical solution for the 2-site Bloch-McConnell equations. It originates as optimization function number 1 from the fitting_main_kex.py script from Mathilde Lescanne, Paul Schanda, and Dominique Marion (see U{http://thread.gmane.org/gmane.science.nmr.relax.devel/4138}, https://web.archive.org/web/gna.org/task/?7712#comment2 and U{https://gna.org/support/download.php?file_id=18262}).

Related models

The NS CPMG 2-site 3D model is a parametric restriction of this model.

Links

The implementation of the NS CPMG 2-site 3D full model in relax can be seen in the:

• relax manual,
• API documentation,
• relaxation dispersion page of the relax website.