Problems during copper (II) oxide data treatment
Hi everyone, I’m having problems during the data treatment. The two samples (please find the project attached with the as-obtained data only, not with the following treatment) are of CuO (copper (II) oxide) were measured in a row and both were measured together with a reference (Cu foil). I have some doubts: 1) The first thing that I did was to calibrate the Reference of the first measurement (peak at maximum of first derivative). Next, I aligned the second Reference keeping the first reference as standard. Did I do correctly until now? 2) I removed the glitches that appeared in the pre-edge (1 glitch) and the EXAFS region (3 glitches) in both measurements. 3) Next, I set the E0 for both samples in the background removal session to set the 0 (zero) point in chi(k). However, when I plot chi(k) the samples profile in high k values differ. I think that they should be at least very close considering that both are the same copper oxide standard and measured in sequence. Am I correct? 4) I've also noticed that the first measurement (Cu_o_2), when plot in chi(R) has a small (but significant) peak positioned at R = 1, which seems not be right, as bond distances are bigger (> 1.5, for example). Is there anything wrong or missing at background removal treatment? I know that it seems novice doubts but as I’m new to XAFS, it really intrigues me. Best regards, Pedro Martins
Here follow the data (please find attached).
2015-09-23 23:46 GMT-03:00 Pedro F B D Martins
Hi everyone, I’m having problems during the data treatment. The two samples (please find the project attached with the as-obtained data only, not with the following treatment) are of CuO (copper (II) oxide) were measured in a row and both were measured together with a reference (Cu foil). I have some doubts:
1) The first thing that I did was to calibrate the Reference of the first measurement (peak at maximum of first derivative). Next, I aligned the second Reference keeping the first reference as standard. Did I do correctly until now?
2) I removed the glitches that appeared in the pre-edge (1 glitch) and the EXAFS region (3 glitches) in both measurements.
3) Next, I set the E0 for both samples in the background removal session to set the 0 (zero) point in chi(k). However, when I plot chi(k) the samples profile in high k values differ. I think that they should be at least very close considering that both are the same copper oxide standard and measured in sequence. Am I correct?
4) I've also noticed that the first measurement (Cu_o_2), when plot in chi(R) has a small (but significant) peak positioned at R = 1, which seems not be right, as bond distances are bigger (> 1.5, for example). Is there anything wrong or missing at background removal treatment?
I know that it seems novice doubts but as I’m new to XAFS, it really intrigues me.
Best regards,
Pedro Martins
Pedro,
I believe you can learn a lot from Bruce's video lectures, see http://www.diamond.ac.uk/Beamlines/Spectroscopy/Techniques/XAS.html
The peak at 1A is due to your improper background removal. After you see Bruce's lectures, you will be one step closer to be an XAFS expert.
Good luck!
2015-09-24
Guanghui
发件人：Pedro F B D Martins
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Guanghui Zhang -
Pedro F B D Martins