XPS peak-fitting reference
Select an element for handbook binding energies, expected chemical-state shifts, spin–orbit splitting, branching ratios, and recommended constraints when fitting XPS spectra. 94 elements in the database.
s-blockp-blockd-blockf-blockselectedColored cells with bold symbols have reference data.
Carbon (C) — Z=6
Reference binding energies, spin–orbit parameters, and recommended constraints for XPS peak fitting.
C 1s
singlet
handbook BE 284.8 eVPrimary BE
284.8 eV
Orbit split (Δ)
n/a
Peak area ratio
n/a
Typical σ / RSF
0.60 eV · RSF 0.25
Peak-fitting constraints
- Primary center: Start near 284.8 eV for the elemental / handbook line; refine within chemical-state windows below.
- Singlet line: C 1s is a singlet — no spin–orbit partner. Do not introduce a linked doublet unless a different orbital is present.
- Typical width (σ): Initial half-width ≈ 0.60 eV; allow modest variation, prefer shared width across related chemical states of the same orbital.
- Relative sensitivity (RSF): Handbook RSF ≈ 0.25 (relative to F 1s = 1.0). Use for quantification, not for constraining peak shape.
- Chemical-state windows: Known states span ~281.6–293.4 eV. Assign each component to a documented state; avoid unconstrained peaks outside this range without justification.
- Background: Use Shirley (or Tougaard) under the fit window; fit peaks on background-subtracted intensity.
Chemical states / expected BE shifts
| State | BE (eV) | Δ vs handbook | Description | Reference |
|---|---|---|---|---|
| TiC | 281.6 | -3.2 | — | Ramqvist1969 |
| WC | 282.2 | -2.6 | — | Ramqvist1969 |
| B4C | 282.8 | -2.0 | — | Ramqvist1969 |
| SiC | 283.4 | -1.4 | — | Ramqvist1969 |
| Fe3C | 283.9 | -0.9 | — | Ramqvist1969 |
| Graphite | 284.5 | -0.3 | — | Johansson1973 |
| C-C/C-H | 284.8 | 0.0 | Adventitious/graphitic | Moulder1995 |
| C-N | 286.1 | +1.3 | Amine/cyanide | Vayrynen1976 |
| NaCN | 286.1 | +1.3 | Cyanide | Vayrynen1976 |
| C-O | 286.3 | +1.5 | Alcohol/ether | Moulder1995 |
| C=O | 287.8 | +3.0 | Carbonyl | Moulder1995 |
| O-C=O | 289.0 | +4.2 | Carboxyl/ester | Moulder1995 |
| CaCO3 | 289.6 | +4.8 | — | Christie1983 |
| CO3 | 290.1 | +5.3 | Carbonate | Moulder1995 |
| CF2 | 291.8 | +7.0 | PTFE-like | Beamson1992 |
| Teflon (-CF2-) | 292.2 | +7.4 | — | Clark1971 |
| CF3 | 293.4 | +8.6 | Fluorocarbon | Beamson1992 |
Core-level reference: Moulder1995
Auger lines
Apparent BE for Al Kα (1486.6 eV). Kinetic energy is source-independent.
| Transition | KE (eV) | Apparent BE (eV) | σ (eV) |
|---|---|---|---|
| C KLL | 263.0 | 1223.6 | 2.0 |
Citations used
- [Beamson1992] G. Beamson, D. Briggs, High Resolution XPS of Organic Polymers: The Scienta ESCA300 Database, John Wiley & Sons, Chichester, 1992.
- [Christie1983] A.B. Christie, J. Lee, I. Sutherland, J.M. Walls, Appl. Surf. Sci. 15, 224 (1983). doi:10.1016/0378-5963(83)90018-1
- [Clark1971] D.T. Clark, D. Kilcast, W.K.R. Musgrave, J. Chem. Soc. Chem. Commun., 603 (1971).
- [Johansson1973] G. Johansson, G. Hedman, J. Berndtsson, A. Klasson, M. Nilsson, R. J. Electron Spectrosc. Relat. Phenom. 2, 295 (1973).
- [Moulder1995] J.F. Moulder, W.F. Stickle, P.E. Sobol, K.D. Bomben, Handbook of X-ray Photoelectron Spectroscopy, Physical Electronics, Eden Prairie, MN, 1995.
- [Ramqvist1969] K. Ramqvist, K. Hamrin, G. Johansson, A. Fahlman, C.J. Nordling, J. Phys. Chem. Solids 30, 1835 (1969).
- [Vayrynen1976] J.J. Vayrynen, J. Electron Spectrosc. Relat. Phenom. 22, 27 (1976).
Binding energies and chemical-state assignments are compiled from publicly available handbooks and primary literature. Contact Anibal Boscoboinik to report errors or missing attributions.