How do we judge the quality of charge compensation in high resolution XPS spectrum for a polymer sample ? should the peaks be in their right binding energy ?
Charge corrections in XPS are a heavily debated topic. If you have some peak of whose correct position you are absolutely sure, that can help, but for a "new" sample that of course isn't the case.
Maybe start with this work here:
Article X-ray photoelectron spectroscopy: Towards reliable binding e...
Polymers are typcially taken to have the alphatic component at 285 eV, so you have to adjust the peaks accordingly with this offset.
Good charge compensation will typically have narrow peaks which are well reolved (pass energy dependent of course)
There is no real point of reference for an insulating material for reasons outlined in the paper Jurgen highlights above. However, it should be clear if there is differential charging as all peaks will typically broaden equally due to the chare difference
Often the charging is compensated by referencing the entire spectrum to the carbon sp3 peak between 284.8 and 285eV. If you have both sp3 and sp2 in your sample this will make it more difficult as it is hard to tell were exactly the sp3 peak is located within the C1s region. Changing often causes the peaks to widen as well, making it even more ambiguous. As the entire spectrum is shifted, you can compare other peak locations with literature values, too, if there are other elements than just oxygen and carbon. Another problem is that the peaks can be distorted on the low energy side. At some point you should simply avoid deconvolution of the core-level spectra...
Thanks everyone for your answers. It really helped me getting started.
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