I dont think that sort of Rfactor/Rfree difference at 2.7A is very surprising..
However there may be a scaling problem. If using refmac look at the Rfactor and <F> analysis. Is the <Fcalc> higher or lower than the <Fobs> in general? Or is there an indication that the distribution of <Fobs> is skewed in some way? With such limitd data the scaling can easily be distorted. You might do better to use SCALE SIMPLE if you are using SCALE BULK or vice versa. Eleanor Li Sheng wrote: >*** For details on how to be removed from this list visit the *** >*** CCP4 home page http://www.ccp4.ac.uk *** > > >Hi, dear all, > >Please do me a favour. I ever collected a data set of 2.7A. The space group is >C2. The model fit the 2fofc map and the omit map very well. The R factor is >0.26 now but R free is 0.37 and can not be minished. What kind of error can >cause such a gap between R factor and R free? >Thanks in advance. > > > > > >Sincerely yours, >Li >2006.06.07 > > > > >
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