hyperfine structure (redirected from Hyperfine levels)

hyperfine structure [′hī·pər‚fīn ′strək·chər]

(spectroscopy)

A splitting of spectral lines due to the spin of the atomic nucleus or to the occurrence of a mixture of isotopes in the element. Abbreviated hfs.

---

Hyperfine structure

A closely spaced structure of the spectrum lines forming a multiplet component in the spectrum of an atom or molecule, or of a liquid or solid. In the emission spectrum for an atom, when a multiplet component is examined at the highest resolution, this component may be seen to be resolved, or split, into a group of spectrum lines which are extremely close together. This hyperfine structure may be due to a nuclear isotope effect, to effects related to nuclear spin, or to both. See Isotope shift, Spin (quantum mechanics)

The measurement of a hyperfine structure spectrum for a gaseous atomic or molecular system can lead to information about the nuclear magnetic and quadrupole moments, and about the atomic or molecular electron configuration. Important methods for the measurement of hyperfine structure for gaseous systems may employ an interferometer, or use atomic beams, electron spin resonance, or nuclear spin resonance.