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Protein Data Bank exchange dictionary (pdbx) version 1.0521

_refine.pdbx_pd_Marquardt_correlation_coeff

Name:
'_refine.pdbx_pd_Marquardt_correlation_coeff'

Definition:

   The correlation coefficient between the observed and
   calculated structure factors for reflections included in
   the refinement. This correlation factor is found in the 
   fitting using the Levenberg-Marquardt algorithm to search 
   for the minimum value of chisquare. Almost all computer 
   codes for Rietveld refinement employ the Gauss-Newton algorithm 
   to find parameters which minimize the weighted sum of squares 
   of the residuals.
   A description of the equations is given on
    http://www.water.hut.fi/~tkarvone/fr_org_s.htm

Type: float

Mandatory item: no

Category: refine