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
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Bernhard Rupp
www.ruppweb.org
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