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Nuclear spin and magnetic moment
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Nuclei have spin and magnetic properties.
Nuclei have intrinsic angular momentum and magnetic moments (μ_N = eħ/2m_p, ~1/1836 of the Bohr magneton), giving hyperfine splitting and used in NMR.
Proton spin ½.
Even–even nuclei have spin 0.
In more detail
Nuclei can have spin and magnetic moments, from the spins of their nucleons. These determine how nuclei respond to magnetic fields and are the basis of nuclear magnetic resonance.
Real-world uses
- NMR spectroscopy identifies molecular structure.
- MRI images tissues using nuclear spins.
- Medical imaging depends on the spin and magnetic moment of hydrogen nuclei in the body.
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Frequently asked questions
Do all nuclei have spin?
No. Nuclei with even numbers of protons and neutrons have zero spin.
Why is hydrogen used in MRI?
Its nucleus is a single proton, which has spin and a large magnetic moment.
Why do some nuclei have spin?
Nucleons have intrinsic spin, and the total spin of a nucleus depends on how its protons and neutrons combine.
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Medical uses of radiation · Nuclear shell model · Liquid drop model · Nuclear magnetic resonance · Mössbauer effect · Nuclear waste