First it is always best to refine your model against the highest resolution good quality data that you have available. There was correspondence about the geometric weighting - could you have weighted the Xray data too high and have bad geometry - see previous Emails!
And the Free R seems rather low for the Se data. Did you transfer the same Free R set from the native to the Se data? Eleanor Peng Zhang wrote: > Dear friends, > > Recently, I have solved a structure using mad method. When using the peak > data(2.3A) as the native for structure refinement, the gap between R > factor and R free is big, about 0.1(0.22 and 0.32). I modelled the > selenomethionine but the gap still exists. When I changed the data for a > real native one(2.7A),it seems OK with R=0.24 and Rf=0.28. > > Does anyone have the similar experience? > what should I pay attention to when using the sad/mad data as the native > one for modelling and refinement? > > Thanks in advance. > > >
