I had XANES and EXAFS data of Layered Double Hydroxide sample, and I want to calculate the coordination number of the elements of my sample. so far I do not have any idea how to do. is there any software or calculation method to answer my problem?
Calculation or better 'estimation' of coordination numbers is a very challenging task in EXAFS evaluation and needs a lot of input data. Further you need a lot of experience in EXAFS data evaluation in order to have a 'feeling' on how far you can trust your results. So you should contact the one, who is related to your EXAFS pattern (experimentalist or beam line scientist of your EXAFS data). He/she may provide some analysis tools and may guide you.
Please see the following link around page 16/17 and especially chapter 6 XAFS data modelling:
https://www.google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=11&ved=2ahUKEwjT9aCh9vXlAhUDyqQKHfgKCJI4ChAWMAB6BAgFEAI&url=https%3A%2F%2Fwww.lehigh.edu%2Fimi%2Fteched%2FGlassCSC%2FSuppReading%2FTutorials.pdf&usg=AOvVaw3PFPH6fruh2a3F7J7CKl35
It is mainly done by fitting/modelling of either the EXAFS itself or the Fouriertransform of the first or second shell. But you need a very lot of input data such as the k-dependence of the phase delta(k) and backscatteramplitude f(k).
See for example also:
https://www.google.de/url?sa=t&rct=j&q=&esrc=s&source=web&cd=2&cad=rja&uact=8&ved=2ahUKEwjXu9nr-NTiAhUI6qQKHUlyATwQFjABegQIBBAC&url=http%3A%2F%2Fwww.esrf.eu%2Ffiles%2Flive%2Fsites%2Fwww%2Ffiles%2Fevents%2Fconferences%2F2017%2FUser_Meeting_2017%2FPart%2520II%2520.pdf&usg=AOvVaw3q-ioxaazlIfTKaP2ZVIuK
Dr. Braun and Dr. Martens provided lots of useful information.
I very much agree with suggestion of Dr. Martens, One needs to spend some time (if possible, with the guide of some body who are experienced) in order learn reliably treat the XANES and EXAFS data.
Eventhough the XANES and EXAFS are the two segments of the same data, approach to analysis and interpret them differs a lot.
I only intend to provide you some information regarding the software and codes:
Most representative codes for EXAFS data:
1) GNXAS package:
You can download the code and find some tutorials from the below website:
http://gnxas.unicam.it/pag_gnxas.html
2) Demeter suite:
You can download the suit of programs and find some tutorials from the below website.
https://bruceravel.github.io/demeter/
I STRONGLY RECOMMEND the Lecture Videos (only about the data treatment) which you can find the link in above website.
There are several codes to perform XANES calculations including:
1) MXAN program:
https://www.lnf.infn.it/theory/CondensedMatter/mxan.html
2) FPMS program:
https://www.lnf.infn.it/theory/CondensedMatter/fpms.html
3) FDMNES
http://neel.cnrs.fr/spip.php?rubrique1007&lang=en
It is strongly recommended to lean from experts in order to be able to fully trust the obtained results.
thank you very much for the advice and references. it is all very useful and I had tried to learn the shell fitting method and got some solution to my problem.
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