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第2楼2014/09/05
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1. Same elements in different Chemical states usually will have similar FWHM. But also pay attention for example for C1s peak at its most common C-C peak the FWHM usually is slightly bigger than its other Chemical state because C-C peak is actually overlapping with C-H peak which always presence together with C-C. Anyway, in general, you can still first stick with above 1st statement "same elements in different Chemical states usually will have similar FWHM". It would be good 1st step although not always correct, but at least its a good concept to start-with.
2. When doing curve fitting, follow below steps:
- determine if fitting element is conductor or semi-conductor or insulator. For conductor, curve fit peak shape is asymmetric. If its semi-con or insulator, then peak shape is Gaussian or saying Gauss-Lorentz.
- Look for fixed area ratio if it is p/d/f orbit doublet. For p area ratio between 2p3 and 2p1 peaks are 2:1. For d, ratio is 3:2 and f will be 4:3.
- Again if it is metal doublet peaks, check for instrument handbook for know peaks separation.
- Pay attention if the peak appear is symmetrical. Do not add more peaks and say there is an extra Chem-state unless you have a proof. For example, if you add an extra Chem-state for Metal-Oxide, then you must see the proof in both the metal peak and oxide peak.
- Check standard Chem state spectra when you do the curve fit (from internet resources, instrument handbook...etc)
- etc...etc...After all, experience counts a lot.
***I cannot open your attached file anyway, so cannot give you more opinion about what you said about 2-peaks and 3-peaks...etc.
3. For powder, making it into pellet can make surface flatter and enhance XPS signal. But it is not a must. Again, cannot download and view your file so cannot give more comments.