Doublet Separations #

Cu 2p = 19.8 eV

Cu 3p = 2.4 eV

Common Overlaps for Cu 2p #

I 3p – Pr 3d – Bi 4s – Sb 3s – Mn LMM (Al Ka X-rays)

Common Overlaps for Cu 3s #

Pr 4d – Nd 4d – Al 2s – Pm 4d – In 4s – Ge 3p – I 4p

Auger Energies #

Note – these are listed in KINETIC ENERGY

Cu LMM ≈ 570 eV

Common Binding Energies – Os 4f #

Theory and Background #

• Asymmetry in metallic lineshapes

  • Like Pt and Ir, metallic Os exhibits a strong Doniach–Šunjić asymmetry in its 4f peaks.

  • This makes fitting tricky — naïve Gaussian–Lorentzian fits tend to misassign oxidation states.

• Multiple oxidation states overlapping

  • Os is “multi-valent” in oxides; you can have Os(IV), Os(VI), Os(VIII) present simultaneously.

  • Their 4f signals overlap closely (often <1 eV apart). Deconvolution is nontrivial and sometimes ambiguous.

• Close overlap with Auger features

  • In certain cases, Os Auger lines can fall close to 4f binding energies, complicating background subtraction.

• Surface oxidation / instability

  • Os is notorious for forming OsO₄ under even mild oxidative conditions.

  • This changes the XPS spectrum dramatically, and OsO₄ is volatile (and extremely toxic). Samples can “age” under air and show higher BE shoulders.

• Peak width differences

  • Higher oxidation states of Os tend to broaden the 4f peaks compared to metallic Os.

  • This can look like unresolved multiplets, but it’s mostly due to chemical disorder and shake-up contributions.

Experimental Advice #

• Minimise air exposure. Prepare samples in glovebox or under inert gas if possible; transfer under vacuum or with a sealed capsule.

• Avoid heating in air. Thermal treatments can produce OsO₄ and change surface composition.

• Surface cleanliness: Os is reactive — adventitious species (C/O) and thin oxide layers form quickly. Document handling history.

• If you must sputter-clean, be careful: Common Ar⁺ sputtering tends to reduce Os oxides and can change oxidation states. Prefer low-energy sputtering or cluster-ion sputtering (gas-cluster, if available) and validate effects on reference samples first.

Data Analysis Guidance #

• Always use asymmetric line shapes (e.g. Doniach–Šunjić) for metallic Os.

• Constrain the 4f spin–orbit splitting (~2.9 eV) and area ratio (4f₇/₂ : 4f₅/₂ ≈ 4:3).

• Be cautious when assigning oxidation states — Os(IV) vs Os(VI) differences can be <1 eV.

• Cross-check with O 1s region (lattice vs oxide oxygen) and possibly XAS if available.

Reference Datasets #

Coming soon

References #