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Spin–orbit coupling
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Interaction creating fine structure.
The electron's magnetic moment interacts with the magnetic field produced by its orbital motion, splitting energy levels (fine structure). Larger for heavy atoms.
Sodium D lines at 589.0 and 589.6 nm.
Relativistic effect.
In more detail
Spin-orbit coupling is the interaction between an electron's spin and its orbital motion, which splits atomic energy levels into fine-structure components.
Real-world uses
- Spin-orbit coupling explains fine structure in hydrogen and heavier atoms.
- It is important in heavy-element chemistry and spintronics.
- Atomic physicists explain the fine structure of hydrogen lines using the coupling between spin and orbital motion.
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Frequently asked questions
Why is it stronger in heavy atoms?
Because the electric fields near the nucleus are larger, increasing the coupling.
What is fine structure?
Small energy splittings of atomic levels caused by spin-orbit coupling and relativistic effects.
What is fine structure?
Small splittings of energy levels caused by spin–orbit coupling and relativistic effects.
Related topics in Quantum Mechanics
Identical particles · Angular momentum in QM · Addition of angular momenta · Zeeman effect · Stark effect · Perturbation theory