Re: FW: [ccp4bb]: Estimated error or occupancy (again)

["Eleanor J. Dodson" <ccp4@ysbl.york.ac.uk>]

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 I have done this for 1 CA, 1 CL atom - using very high resolution data.

( 1G4I if anyone else wants to try..)

Here the initial coordinates are:
ATOM     CA     0.35550   0.08872   0.65881    1.00 0.0 BFAC      6.590
ATOM     CL     0.37950   0.40896   0.49112    0.69 0.0 BFAC     10.090

 with occupancies 1.00 and 0.69

After running mlphare on the centric data only ( P212121 so there is
lots of it) I get 
DERIV     ca cl
DCYCLE PHASE ALL REFCYC ALL KBOV ALL
RESO      10.00      1.00
SCALE    FPH1    0.9886    0.0110
ISOE      128.48   45.46   25.82   16.06    8.55    5.54    4.09    2.84
ATOM1    CA    0.355  0.089  0.659  1.007 BFAC    6.492
ATREF X ALL Y ALL Z ALL OCC ALL AOCC ALL B ALL
ATOM2    CL    0.379  0.409  0.491  0.772 BFAC   10.152
ATREF X ALL Y ALL Z ALL OCC ALL AOCC ALL B ALL


 ie the occupancies and B have hardly changed.


HOWEVER the low resolution data does not agree at all well, and maybe in
some of the other cases there is only low resolution data to use? 

The output scaled F from refmac5 has been multiplied by the overall
scale but there has been no correction for aniso B terms.

This may really matter with lower resolution data.

As you can see here ,the "FPH" scale is stiull nearly 1, but is that
always so?

Eleanor

Incidently it does give SDs

Compound 1   "ca cl"
 -----------------------------
 Scale Factor                    0.9859   Shift    0.0000    S. D.   
0.0037
 Overall B                       0.0279   Shift    0.0000    S. D.    
0.026

 Site:   1   CA  
     Real Occupancy               1.018   Shift     0.0001   S. D.    
0.012
     Temp. Factor                 6.590
     Atomic Coordinates         0.35542   0.08866   0.65883
     Coordinate Shift           0.00000   0.00000  
0.00000                      
    S. D. of Coordinate Shift   0.00009   0.00006  
0.00012                      

 Site:   2   CL  
     Real Occupancy               0.761   Shift     0.0005   S. D.    
0.021
     Temp. Factor                10.090
     Atomic Coordinates         0.37953   0.40867   0.49114
     Coordinate Shift           0.00000   0.00000  
0.00000                      
    S. D. of Coordinate Shift   0.00024   0.00017  
0.00032                      


 Rivals small molecules!
Eleanor

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