Chlorine #
Orbitals and Energies #
Note – these are listed in BINDING ENERGY
Cl 1s ≈ 2830 eV (HAXPES)
Cl 2s ≈ 270 eV
Cl 2p ≈ 190 eV
Cl 3s ≈ 18 eV
Cl 3p ≈ 7 eV
Doublet Separations #
Cl 2p = 1.6 eV
Common Overlaps for Cl 2p #
Ra 5p – As 3d – Nb 3d – Lu 4d – La 4p – Ce 4p
Theory and Background #
Chlorine XPS analysis very straightforward and is typically performed on the 2p region where overlaps are restricted to the Se LMM auger and As 3s photoemission.
Cl 2p peaks have a doublet separation of 1.6 eV.
Experimental Advice #
Chlorine is a common contaminant in XPS, typically from NaCl salts from sweat on poorly handled samples. Always wear gloves when handling XPS samples!
Chlorine polymers have been observed to degrade under continual X-ray exposure, be sure to take a quick scan before and after full measurement to check for degradation of an new or unknown sample.[14]
Data Analysis Guidance #
Cl 2p is easily fit with a typical Voight-type lineshape.
References #
- Spectrum recorded by HarwellXPS
- Lannon Jr, J. M. and Q. Meng (1999). “Analysis of a Filled Poly (vinyl chloride) Polymer by XPS.” Surface Science Spectra 6(2): 131-136. Read it online here.
- Beard, B. C. (1993). “Sodium salts of chlorine oxyacid anions, Cl (+ 7), perchlorate, XPS comparison spectra.” Surface Science Spectra 2(2): 97-103. Read it online here.
- Garbassi, F. and L. Pozzi (1979). “Electron beam effects on hydrated magnesium chloride revealed by XPS.” Journal of Electron Spectroscopy and Related Phenomena 16(2): 199-203. Read it online here.
- Mousty‐Desbuquoit, C., et al. (1983). “Solid state effects in the electronic structure of TiCl4 studied by XPS.” The Journal of chemical physics 79(1): 26-32. Read it online here.
- Piao, H., et al. (2004). “A temperature-programmed X-ray photoelectron spectroscopy (TPXPS) study of chlorine adsorption and diffusion on Ag (1 1 1).” Surface science 557(1-3): 13-20. Read it online here.
- Vasquez, R. P. (1993). “CuCl2 by XPS.” Surface Science Spectra 2(2): 160-164. Read it online here.
- Vasquez, R. P. (1993). “CuCl by XPS.” Surface Science Spectra 2(2): 138-143. Read it online here.
- Vasquez, R. P. (1992). “SrCl2 by XPS.” Surface Science Spectra 1(1): 68-74. Read it online here.
- Militello, M. C. and S. J. Simko (1994). “Palladium chloride (PdCl2) by XPS.” Surface Science Spectra 3(4): 402-409. Read it online here.
- Beard, B. C. (1993). “Fresh cleaved single crystal NaCl, XPS spectra, Al source.” Surface Science Spectra 2(2): 91-96. Read it online here.
- Beard, B. C. (1993). “Sodium Salts of Chlorine Oxyacid Anions, Cl (+ 5), Chlorate, XPS Comparison Spectra.” Surface Science Spectra 2(1): 26-30. Read it online here.
- Beard, B. C. (1993). “Sodium Salts of Chlorine Oxyacid Anions, Cl (+ 3), Chlorite, XPS Comparison Spectra.” Surface Science Spectra 2(1): 20-25. Read it online here.
- Morgan, David J., and Sharukaa Uthayasekaran. “Revisiting degradation in the XPS analysis of polymers.” Surface and Interface Analysis 55.6-7 (2023): 556-563. Read it online here.
