Chromium - 24Cr: properties of free atoms
Chromium atoms have 24 electrons and the shell structure is 2.8.13.1.
The ground state electron configuration of ground state gaseous neutral chromium is [Ar].3d5.4s1 and the term symbol is 7S3.
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Atomic spectrum
A representation of the atomic spectrum of chromium.
Ionisation Energies and electron affinity
The electron affinity of chromium is 64.3 kJ mol‑1. The ionisation energies of chromium are given below.
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Effective Nuclear Charges
The following are "Clementi-Raimondi" effective nuclear charges, Zeff. Follow the hyperlinks for more details and for graphs in various formats.
1s | 23.4138 | ||||||
---|---|---|---|---|---|---|---|
2s | 16.98 | 2p | 20.08 | ||||
3s | 12.37 | 3p | 11.47 | 3d | 9.76 | ||
4s | 5.13 | 4p | (no data) | 4d | (no data) | 4f | (no data) |
5s | (no data) | 5p | (no data) | 5d | (no data) | ||
6s | (no data) | 6p | (no data) | ||||
7s |
References
These effective nuclear charges, Zeff, are adapted from the following references:
- E. Clementi and D.L.Raimondi, J. Chem. Phys. 1963, 38, 2686.
- E. Clementi, D.L.Raimondi, and W.P. Reinhardt, J. Chem. Phys. 1967, 47, 1300.
Electron binding energies
Label | Orbital | eV [literature reference] |
---|---|---|
K | 1s | 5989 [1] |
L I | 2s | 696 [3] |
L II | 2p1/2 | 583.8 [3] |
L III | 2p3/2 | 574.1 [3] |
M I | 3s | 74.1 [3] |
M II | 3p1/2 | 42.2 [3] |
M III | 3p3/2 | 42.2 [3] |
Notes
I am grateful to Gwyn Williams (Jefferson Laboratory, Virginia, USA) who provided the electron binding energy data. The data are adapted from references 1-3. They are tabulated elsewhere on the WWW (reference 4) and in paper form (reference 5).
References
- J. A. Bearden and A. F. Burr, "Reevaluation of X-Ray Atomic Energy Levels," Rev. Mod. Phys., 1967, 39, 125.
- M. Cardona and L. Ley, Eds., Photoemission in Solids I: General Principles (Springer-Verlag, Berlin) with additional corrections, 1978.
- Gwyn Williams WWW table of values
- D.R. Lide, (Ed.) in Chemical Rubber Company handbook of chemistry and physics, CRC Press, Boca Raton, Florida, USA, 81st edition, 2000.
- J. C. Fuggle and N. Mårtensson, "Core-Level Binding Energies in Metals," J. Electron Spectrosc. Relat. Phenom., 1980, 21, 275.