Hi Abney: What you need to do is 1. Import the data for each scan. 2. if you have multiple scans for each sample, verify that they are all aligned (that is that the monochromator energy calibration has not changed) by comparing the edge of all of the reference channels (if you have reference) or the data scans themselves. 3. If they all align, just skip to step 5 below, if they do not, then ... 4. Align all the scans by aligning the derivatives or whatever method you want to us (experiment...) 5. Merge all the data 6. take the merged data set and make sure that the edge position is where you want it, usually at the peak in the first derivative of the edge jump. That is it. When you are doing the fitting, allow E0 to vary and if it is too big, go back to the data and adjust it because it is likely that you assined it incorrectly. Carlo On Thu, 5 Jun 2014, Carter Abney wrote:

Edmund & Drew, thanks for your insights on the matter. I think between the combination of your responses, things are making more sense.

Edmund, your question "Why?" is valid. The answer is: "I misunderstood what was being done in the tutorials/literature." There is plenty of documentation discussing E0 correction, I'm just new to EXAFS and thought this is what I was trying to do in the alignment menu (and thought this is what they were asking for in the tutorials, etc). Drew, as you pointed out I don't actually want to adjust the whole spectrum in energy, just the position of E0 to better align the experimental data to the theoretical first shell.

So, to answer my own question (and make sure I'm actually understanding you): 1.) I imported the data acceptably, but 2.) should adjust the E0 value for the experimental data by changing the pre-edge range, normalization range, and Rbkg. I should be able to see the effects of these changes by plotting in k-space with my imported theoretical first shell.

Someone please (re)correct me if I'm still not getting it right. Thanks again for the help.

- Carter

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