I have synthesized Hydroxyapatite and Strontium Hydroxyapatite(no substitution, in pure form). In former case, there is no splitting of P2p splitting, but in later, there is a splitting. Why is this so. Does not Phosphorous should show doublet behavior in its fine scan?
The transition for ds=0 is commonly forbidden one, however it become allowed transition due to the spin-orbit coupling in Strontium Hydroxyapatite.
This is probably related to different FWHMs of your peaks and would be easier to judge if you can show us the spectra. The spin-orbit splitting of P2p is relatively small (0.87 eV), so depending on the resolution of your setup and the intrinsic width of your peaks you might be able to observe it or not.
Thorsten Schultz it is a fine scan with 0.1eV scaling. Here is the graph. moreover in second case, the Sr 3d and P2p energy range overalps, so the same spectrum I see for P2p and Sr3d.
So you have a slight asymetry on the high binding energy side for your first image, due to the P2p spin-orbit splitting. I think the left peak in the second image is the Sr 3d_3/2 peak and the Sr 3d_5/2 peak overlaps with the P 2p peak. If you send me the raw data I can attempt a peak fitting.
Thorsten Schultz my question is not resolved, why is this behavior being observed for two Phosphorous material P2p orbital. My logic says as there is Sr content, that's why this is the case. Even though P2p energy difference is 0.87 eV, the fine scan scale is 0.1 eV. I read somewhere that the P2p data given by normal XPS do not reflect the actual binding energy as its actual binding energy is 1900 eV and the Al has lower than that. So I have this issue too?
I hope my fits of your data make it clear. You have the P2p spin orbit splitting in both cases and the Sr3d strongly overlapping the P2p peak in case of the strontium hydroxyapatite.
Your step size has nothing to do with your resolution.
I don't know what you are referring to with 1900 eV. The P1s core level peak would be at ~2150 eV, this you can indeed not measure with Al excitation.
Thorsten Schultz thanks for the fit. I wanted to know why even resolution is 0.1 eV but doublet behavior is not visible significantly (I know in the fitting we have the two but as P2p has 0.97 eV, the splitting must be seen). Is there any reason for this?
You are confusing your step width with your energy resolution. Your setup resolution is a combination of the energy width of your excitation source and the energy resolution of your detector and is in the order of 0.3-0.5 eV for monochromatic sources and 0.8-1 eV for non-monochromatic sources.
Thorsten Schultz can you tell me did you get 3:1 ratio for the first case as I am getting 2.5 as ratio for 2p1/2 and 2p3/2 for phosphorous by xpspeak41 software
I'm getting a 2:1 ratio, since that's how you have to constrain the peak areas due to the spin orbit splitting. I suggest you read some XPS peak fitting guides for beginners before you attempt and further deconvolutions.
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