Chi eff.m

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Finds the optimal magnetic susceptibility tensor that a user-supplied paramagnetic centre probability density must have in order to fit the PCS data supplied. Syntax:

       [chi,pred_pcs]=chi_eff(source_cube,ranges,nxyz,expt_pcs)

Parameters:

 source_cube - paramagnetic centre probability density cube

      ranges - a six-element vector giving the extents of the
               probability density cube in Angstroms as
               [xmin xmax ymin ymax zmin zmax]

        nxyz - nuclear coordinates as [x y z] with multiple rows,
               at which PCS is measured, in Angstroms.

    expt_pcs - pseudocontact shift in ppm at each nucleus.

Outputs:

    chi      - optimized magnetic susceptibility tensor in cubic
               Angstroms.
    pred_pcs - predicted pseudocontact shift at each nucleus with
               the optimized mxyz and chi, ppm.