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  • major reference

    reaction mechanism: Kinetic isotope effects
  • atomic spectra

    spectroscopy: Perturbations of levels
    ...of nuclei and the distribution of the electron clouds near nuclei. Systematic changes in level positions are seen as the number of neutrons in a nucleus is increased. These effects are known as isotope shifts and form the basis for laser isotope separation. For light atoms, the isotope shift is primarily due to differences in the finite mass of the nucleus. For heavier atoms, the main...
  • description and properties

    isotope: Physical properties associated with isotopes
  • hydrogen isotopes and reaction rate

    hydrogen (H): Isotopes of hydrogen
  • hyperfine structure

    hyperfine structure (HFS)
    A similar effect of line splitting is caused by mass differences (isotopes) of atoms in an element and is called isotope structure, or isotope shift. These spectral lines are sometimes referred to as hyperfine structure but may be observed in an element with spin-zero isotopes (even atomic and mass numbers). Isotope structure is seldom observed without true HFS accompanying it.
  • superconductivity

    BCS theory
    ...the BCS theory. The theory supplies a means by which the energy required to separate the Cooper pairs into their individual electrons can be measured experimentally. The BCS theory also explains the isotope effect, in which the temperature at which superconductivity appears is reduced if heavier atoms of the elements making up the material are introduced.
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