[RMCProfile-users] EXAFS example

[Levin, Igor]

Dear Carlos,

The existing version of RMCProfile lets you fit your EXAFS data in either  r or k spaces.  It also lets you to weigh your data by any power of k.

There is no limit on the number of atoms in the configuration box other than those imposed by the computational speed.  We routinely fit configurations of about 20,000 atoms.  I don’t understand your choice of a supercell with only 256 atoms.    The fitting range in this case will be limited to just a few angstrom.

The RMCProfile package includes utility programs that use your configuration file to generate lists of absorbers and scatterers for the scattering paths of interest.  In case of absorbers having distinct coordination numbers, you may need to specify each of these as a separate type.

Preferably, the background should be subtracted in Athena prior to fitting the data in RMCProfile.

It’s difficult to give you a more specific advise without knowing details of your problem.

Best regards,

Igor


From: rmcprofile-users [mailto:rmcprofile-users-bounces at rmcprofile.org] On Behalf Of Carlos Triana Estupinan
Sent: Wednesday, March 18, 2015 6:39 AM
To: rmcprofile-users at rmcprofile.org
Subject: Re: [RMCProfile-users] EXAFS example

Dear
Helen

Thanks so much for your kind answer.
Yes, I have EXAFS data ready to run RMC in order to model the amorphous structure of oxides. However, I am not sure if I have to fit the FFT in the real espace (chi(k^-3) vs R (A)), or the k space representations (k^-3(chi(k)) vs K(A^-1)).
Also,
for me it is not clear if it is possible to model a supercell with around 256 atoms or more.
If I have around 80 absorbers in different cartesian position who can I define those absorbers in the file. What about if the local environment is different, for example one absorber bounded with 4,5,6,7,8 oxygen atoms.
After data manipulation shall I fitt also the background and the others spectra obtained by artemis or athena.
I know these are a lot of questions, and I know you are busy, but for me it is very important to carry out these modellations.

Thanks so much for your help

best regards

2015-03-02 12:50 GMT+01:00 <helen.playford at stfc.ac.uk<mailto:helen.playford at stfc.ac.uk>>:
Dear Carlos,

We’ve recently been working on updating the EXAFS tutorial and that will be available in a future release (hopefully soon) so the examples mentioned in the EXAFS manual are not really applicable at present. If you have EXAFS data ready and are keen to get going, please drop me an email and we can discuss off-the-list the best way forward.

Best wishes,
Helen

From: rmcprofile-users [mailto:rmcprofile-users-bounces at rmcprofile.org<mailto:rmcprofile-users-bounces at rmcprofile.org>] On Behalf Of Carlos Triana Estupinan
Sent: 19 February 2015 21:31
To: rmcprofile-users at rmcprofile.org<mailto:rmcprofile-users at rmcprofile.org>
Subject: [RMCProfile-users] EXAFS example

DEAR
RMC group

I want to know how can I get the files necessaries to run the EXAFS examples, since those files no appear in the folder I download months ago. Could you please tell me how can I get those files.

best


--

Carlos Augusto Triana Estupiñan (C.A. Triana-E)
Physicist
M.Sc. In Physical Sciences-Research
PhD Student-Research
Ångströmlaboratoriet, Lägerhyddsv. 1
Solid State physics
Uppsala University, Box 534
751 21 Uppsala, Sweden
Tel: +46 018 471 3144
e-mail:carlos.triana at angstrom.uu.se<mailto:e-mail%3Acarlos.triana at angstrom.uu.se>
web:http://www.uu.se/

_______________________________________________
rmcprofile-users mailing list
rmcprofile-users at rmcprofile.org<mailto:rmcprofile-users at rmcprofile.org>
http://lists.rmcprofile.org/mailman/listinfo/rmcprofile-users



--

Carlos Augusto Triana Estupiñan (C.A. Triana-E)
Physicist
M.Sc. In Physical Sciences-Research
PhD Student-Research
Ångströmlaboratoriet, Lägerhyddsv. 1
Solid State physics
Uppsala University, Box 534
751 21 Uppsala, Sweden
Tel: +46 018 471 3144
e-mail:carlos.triana at angstrom.uu.se<mailto:e-mail%3Acarlos.triana at angstrom.uu.se>
web:http://www.uu.se/
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://lists.rmcprofile.org/pipermail/rmcprofile-users/attachments/20150318/84855ff8/attachment.html>