Dear All, 

there is one line in the TRUNCATE output that makes
me question my sanity.

Under the Wilson plot the log states:
 
Least squares straight line gives:   B  = 12.743        SCALE  =  22.25070
where  F(absolute)**2 = SCALE*F(observed)**2*EXP(-B*2*SINTH**2/L**2)

This is somewhat counterintuitive, because in order to get the 
attenuated reflections fobs**2 *UP* to the unattenuated fabs**2 I would
assume that I have to multiply with the inverse of the B-factor attenuation,
EXP(B*2*SINTH**2/L**2)

If I look at the plot, then plot is indeed from a graph
ln[(fobs**2)/fabs**2] = ln(k)-2B(sintol**2)

thus  

ln(fobs**2)=ln(fabs**2)+ln(k)-2B(sintol**2) =

fobs**2 =k*(fabs**2)*exp(-2B(sintol**2))

which essentially is the opposite of what truncate says,
I thus wonder if the inverse expression for bringing
relative to absolute intensities, i.e., scaling back
should be in truncate terms

F(absolute)**2 = SCALE*F(observed)**2*EXP(B*2*SINTH**2/L**2)

I know this is for sure the right way to bring
fobses back up to unitary Us and normalized Es.
 
What am I missing here? 

Thx, br
--------------------------------------------
Bernhard Rupp
www.ruppweb.org              
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