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Atomic Spectroscopy - A Compendium of Basic Ideas, Notation, Data, and Formulas

Version History

W. C. Martin and W. L. Wiese
National Institute of Standards and Technology
Gaithersburg, Maryland 20899

Note for Macintosh Users: Due to differences in many Macintosh browsers, the spectroscopic notation of this article may appear with unintended spacing on a Mac©. A PDF version (705 kB) of this article may be used instead. The table of Ground levels and ionization energies for the neutral atoms is also available.

  1. Introduction
  2. Frequency, Wavenumber, Wavelength
  3. Atomic States, Shells, and Configurations
  4. Hydrogen and Hydrogen-like Ions
  5. Alkalis and Alkali-like Spectra
  6. Helium and Helium-like Ions; LS Coupling
  7. Hierarchy of Atomic Structure in LS Coupling
  8. Allowed Terms of Levels for Equivalent Electrons 
  9. Notations for Different Coupling Schemes
  10. Eigenvector Composition of Levels
  11. Ground Levels and Ionization Energies for the Neutral Atoms
  12. Zeeman Effect
  13. Term Series, Quantum Defects, and Spectral-line Series
  14. Sequences
  15. Spectral Wavelength Ranges, Dispersion of Air
  16. Wavelength (Frequency) Standards
  17. Spectral Lines: Selection Rules, Intensities, Transition Probabilities, Values, and Line Strengths 
  18. Atomic Lifetimes
  19. Regularities and Scaling
  20. Spectral Line Shapes, Widths, and Shifts
  21. Spectral Continuum Radiation
  22. Sources of Spectroscopic Data
  23. References


Created July 9, 2009, Updated November 15, 2019