Orbitals and Energies #
Note – these are listed in BINDING ENERGY
Bi 4s ≈ 939 eV
Bi 4p ≈ 679 eV
Bi 4d ≈ 440 eV
Bi 4f ≈ 158 eV
Bi 5s ≈ 160 eV
Bi 5p ≈ 93 eV
Bi 5d ≈ 25 eV
Bi 6s ≈ 8 eV
Bi 6p ≈ 3 eV
Doublet Separations #
Bi 4f = 5.3 eV
Bi 4d = 23.5 eV
Bi 4p = 126.6 eV
Bi 5d = 3.1 eV
Bi 5p = 26.3 eV
Common Overlaps for Bi 4f #
Ga 3s – Se 3p – Te 4s – Ac 5p – S 2p – Rn 5p – Se 3p – Cs 4p – Y 3d – Dy 4d – Ra 5p
Theory and Background #
Shake-up satellites and plasmon loss features commonly appear in bismuth XPS spectra due to electronic excitations and collective electron oscillations, respectively. For example, Bi surface and bulk plasmons have been identified near energy losses of ~14.7 to 16.5 eV, influencing peak shapes and satellite structures.
Experimental Advice #
Bismuth (III) is known to reduce when exposed to X-rays for a significant period,[4] so it would be advisable to perform reduction checks (single scans before and after the experiment) to check the bismuth is not affected by the measurement.
See our page on sample damage for more information.
Ion etching may also reduce bismuth species during depth profiles to the metal following prolonged exposure.[5] Keep this in mind when performing depth profiles, and potentially consider options to account for this reduction (e.g. HAXPES).
If sulfur is present, it may be helpful to record the S 2s peak too to help account for the S 2p – Bi 4f overlap.
Data Analysis Guidance #
Bi metal does not exhibit a huge amount asymmetry, while oxides and compounds are symmetric in nature.
References #
- Dharmadhikari, Vineet S., et al. “Characterisation of thin films of bismuth oxide by X-ray photoelectron spectroscopy.” Journal of Electron Spectroscopy and Related Phenomena 25.2 (1982): 181-189. Read it online here.
- Rodriguez-Pereira, Jhonatan, Sergio A. Rincón-Ortiz, and Rogelio Ospina. “Bismuth acetate by XPS.” Surface Science Spectra 27.2 (2020). Read it online here.
- Shallenberger, Jeffrey R., et al. “2D bismuth telluride analyzed by XPS.” Surface Science Spectra 26.2 (2019). Read it online here.
- Süzer, Şefik. “XPS investigation of X-ray-induced reduction of metal ions.” Applied Spectroscopy 54.11 (2000): 1716-1718. Read it online here.
- Zhi-Cheng, Jiang, An Li-Dun, and Yin Yuan-Gen. “XPS study of ion-induced chemical effect on β-bismuth molybdate catalyst.” Applied surface science 24.2 (1985): 134-146. Read it online here.
