[Ifeffit] Query regarding measurement uncertainity

Bruce Ravel bravel at bnl.gov
Mon Jan 26 08:44:31 CST 2009

On Monday 26 January 2009 09:28:08 am Bindu R. wrote:
> I have one doubt regarding the measurement uncertainty in R- space (εR). In
> the manual it is written that εR is evaluated from the rms value of FT in
> the range 15-20 Å. My doubt is.....
> In case the FT in R-space does not extend up to the range mentioned above,
> then how does the fitting program choose the value of εR?

The case where there is no signal in the very-high-R range is the case
in which this approximation is most valid.  If there is no EXAFS above
15 A, then the only source of non-zero spectral weight is noise.



 Bruce Ravel  ------------------------------------ bravel at bnl.gov

 National Institute of Standards and Technology
 Synchrotron Methods Group at NSLS --- Beamlines U7A, X24A, X23A2
 Building 535A
 Upton NY, 11973

 My homepage:    http://xafs.org/BruceRavel
 EXAFS software: http://cars9.uchicago.edu/~ravel/software/exafs/

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