[Ifeffit] Fwd: Re: Use of feff8 with D-artemis?

[Bruce Ravel]

On Thursday, July 12, 2012 05:31:19 PM you wrote:
> 
> I wonder why the new Artemis (from Demeter) is limited to feff6 or feff7 as
> the old ifeffit can deals with feff8 and feff9.
>
> Is it a wish? When you published data using feff7, the reviewers first note
> that you should have used more actual version.

I would challenge a reviewer to come up with a reliable study
demonstrating that Feff8 or Feff9 provides a statistically significant
improvement to EXAFS analysis.  Obviously, I am not saying that full
multiple scattering, self-consistency, and the various potential
improvements in Feff9 are not relevant to XANES calculations or to
Feff's treatment of other spectroscopies.  What I am saying is that it
has not been rigorously demonstrated that those things have an impact
on the calculation of the extended EXAFS such that the analysis is
improved in a statistically meaningful way.

In short, I find that such arguments from reviewers boil down to
"Feff8 is 33% better than Feff6 because 8 is 33% bigger than 6!"
 
> Is it planned that D-Artemis will work with feff8 too?
> 
> I am using the other programs of Demeter but still have to stick to the old
> Artemis as none of my files can be read by D-Artemis (always error due to
> feff8 or feff9 files by importing old project)

That said, there is no good reason that artemis should not be able to
use Feff8 or 9 if you want to do so.  I suppose that laziness is the
best explanation for why it doesn't yet.

The Atoms portion of Demeter writes Feff8 files.  The Atoms portion of
Artemis simply has the line of code for using that part of Demeter
commented out.  That's trivial to fix.

Getting Demeter to use Feff8 instead of Feff6 is not a lot of work,
but it is also not a trivial amount of work.

I will put this at the top of my to do list.  Given that I will soon
be leaving for conferences in distant places on the globe, I probably
won't be able to release a version of Demeter that uses Feff8
effectively until Spetember.

B


-- 

 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

 Homepage:    http://xafs.org/BruceRavel
 Software:    https://github.com/bruceravel
-----------------------------------------


-- 

 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

 Homepage:    http://xafs.org/BruceRavel
 Software:    https://github.com/bruceravel