X-ray notation
X-ray notation is a method of labeling atomic orbitals that grew out of X-ray science. It is still traditionally used with most x-ray spectroscopy techniques including AES and XPS. In X-ray notation, every principal quantum number is given a letter associated with it.
Conversion
Conversion[1][2]
Quantum Numbers
(n l s j) |
Atomic Notation |
X-ray Notation |
| 1 0 ±1/2 1/2 |
1s(1/2) |
K1 |
| 2 0 ±1/2 1/2 |
2s(1/2) |
L1 |
| 2 1 -1/2 1/2 |
2p(1/2) |
L2 |
| 2 1 +1/2 3/2 |
2p(3/2) |
L3 |
| 3 0 ±1/2 1/2 |
3s |
M1 |
| 3 1 -1/2 1/2 |
3p1/2 |
M2 |
| 3 1 +1/2 3/2 |
3p3/2 |
M3 |
| 3 2 -1/2 3/2 |
3d3/2 |
M4 |
| 3 2 +1/2 5/2 |
3d5/2 |
M5 |
Use
- X-ray sources are classified by the type of material and orbital used to generate them. For example, CuKα X-rays are emitted from the K orbital of copper.
- X-ray absorption is reported as which orbital absorped the x-ray photon. In EXAFS and XMCD the L-edge or the L absorption edge is the point where the L orbital begins to absorp x-rays.
- Auger peaks are identified with three orbital definitions, for example KL1L2. In this case, K represents the core level hole, L1 the relaxing electron's initial state, and L2 the emitted electron's initial energy state.
References