Hi Samer,
I am CCing my response to the Ifeffit mailing list. I ask that
questions about the software be directed to the mailing list rather
than to me personally.
The file that you attached is from the SSRL Data Collector. This is
one of the formats supported by a filetype plugin. See
http://cars9.uchicago.edu/~ravel/software/doc/Athena/html/import/plugin.html
As explained on that page, from the "Settings" menu, select "Plugin
registry", then click on the button labeled "SSRLA". Athena will
then be able to import your file.
If you do not have that plugin on your computer for some reason (for
example, if you are running a somewhat old version of Athena), a copy
can be found at
http://cars9.uchicago.edu/svn/horae/trunk/lib/Ifeffit/Plugins/Filetype/Athe…
Place that file in
C:\Program File\Ifeffit\horae\Ifeffit\Plugins\Filetype\Athena\
if you are a windows user or in
$HOME/.horae/Ifeffit/Plugins/Filetype/Athena/
on linux. There is a similar location on a Mac, but I don't know its
path off the top of my head.
B
On Friday, January 07, 2011 05:46:13 am you wrote:
> Dear Mr. Bruce,
>
>
>
> At first I wish you a happy new year and a very successful 2011!
>
> I have problem with opening the Roble files with Athena (see pleas attached
> file).
>
> I get the following error: the file could not be read by ifeffit as data
> file.
>
> Our Athena version is 0.8.061.
>
>
>
> Could you please help me?
>
>
>
> Thanks in advance.
>
>
>
> With best wishes,
>
>
>
> Samer Amayri
> __________________________________________________________________
> Dr. Samer Amayri
> Institut für Kernchemie
> der Universität Mainz
> Fritz-Strassmann Weg 2
> D-55128 Mainz
> Telefon: +496131 39-25317/25307 (Lab.)
> Handy: 017621805879
> Fax-Nr. +496131 39-24510
> E-mail: amayri(a)uni-mainz.de<mailto:amayri@uni-mainz.de>
--
Bruce Ravel ------------------------------------ bravel(a)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/
Hi Alan,
(To the list: I discussed Alan's system a bit with him when he came to
SSRL, but don't recall the details. That's why in this reply I have a
little more knowledge about it than what he posted yesterday.)
I suspect the peak at 2.3 A does indeed represent structure of some
kind. Your k-space data for sample 1 has very little noise, so I don't
think it's spurious in that sense.
What strikes me about your data is that the FT's have so little
structure beyond the 1.8 A peak. I don't recall exactly the nature of
your system: it was cadmium loaded on to the surface of a substrate,
but I don't recall what the substrate was. If it's low-Z (for example,
silica), then the scattering off of whatever the oxygen is bonded to
(in my example, silicon) would show up pretty weakly, and that could
be the peak at 2.3 A. It's absence in sample 2 could represent the
cadmium ion being less selective about what surface site it bonds to,
so that the Cd-Si distance (in my example) varies and the peak washes
out.
That's all just an example of the kind of thing that could be
responsible for what you're seeing. I agree that a good plan is to use
a Cd-O structure to at least let you model the first peak. For the
second peak, though, you may have to take more inspiration from the
structure of the substrate than the structure of Cd-O.
It's also intriguing that the white line in your sample is larger than
in the CdO standard from the database. Someone with more XANES
experience than I might be able to suggest why that is--something
about these being bound to the surface?
Is my recollection of your system correct? If so, what was the
substrate?
--Scott Calvin
Faculty at Sarah Lawrence College
Currently on sabbatical at Stanford Synchrotron Radiation Laboratory
On Jan 5, 2011, at 11:23 PM, Alan Du wrote:
>
> Hi all,
>
> I processed my XAS data and compare them with standards from Farrel
> Lytle Database. (http://img717.imageshack.us/i/xasw.jpg/)
>
> In the RSF, both sample 1 and 2 has a major peak at R = ca. 1.8 A.
> sample 1 has an additional peak at R = ca. 2.3 A. I wonder if this
> tiny peak is significant.
>
> It seems both samples has peak positions similar to those of CdO
> standard, which sound logical because the cadmium will bind to the
> surface oxygen of the material.
>
> I looking at fitting sample 1 and 2 using whatever crystallographic
> info of CdO I can get my hands on.
>
> Wonder if the plan make sense.
>
> Happy new year,
> Alan
Hi all,
I processed my XAS data and compare them with standards from Farrel Lytle
Database. (http://img717.imageshack.us/i/xasw.jpg/)
In the RSF, both sample 1 and 2 has a major peak at R = ca. 1.8 A. sample 1
has an additional peak at R = ca. 2.3 A. I wonder if this tiny peak is
significant.
It seems both samples has peak positions similar to those of CdO standard,
which sound logical because the cadmium will bind to the surface oxygen of
the material.
I looking at fitting sample 1 and 2 using whatever crystallographic info of
CdO I can get my hands on.
Wonder if the plan make sense.
Happy new year,
Alan
