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Re: [ccp4bb]: r_free problem

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Perhaps you'd better check the number of |Fo|'s used for refinement, the
number of atoms to be refined * 3 (for X, Y, Z coordinates), in order to
check that you are not overfitting the data, I.E. too few reflections for
"classical" refinement in cartesian space.

If that is the case, then the only way around is to reduce the number of
parameters to be refined, i.e. go for refinement in torsion angle space.

If you are "lucky" to have NCS, you can also reduce this number by using
NCS constraints during refinement (i.e. refining only one of the
"constituents", the others being generated by application of the NCS
matrices + vectors.

Hope this helps, you did not give many details...


s-mail: F.M.D. Vellieux (B.Sc., Ph.D.)
        Institut de Biologie Structurale J.-P. Ebel CEA CNRS UJF
        41 Avenue des Martyrs
        38027 Grenoble Cedex 01
Tel:    (+33) (0) 476889605
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e-mail: vellieux@ibs.fr
Don't even think of asking me: "I would              Het leven is genieten
    if I could, but I can't" (L.R., 1998)               (to live is to enjoy)
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