W. C. Martin and W. L. Wiese

National Institute of Standards and Technology
Gaithersburg, Maryland 20899

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Introduction  Frequency, Wavenumber, Wavelength  Atomic States, Shells, and Configurations  Hydrogen and Hydrogen-like Ions  Alkalis and Alkali-like Spectra  Helium and Helium-like Ions; LS Coupling  Hierarchy of Atomic Structure in LS Coupling  Allowed Terms of Levels for Equivalent Electrons  LS Coupling  jj Coupling  Notations for Different Coupling Schemes  LS Coupling (Russell-Saunders Coupling)  jj Coupling of Equivalent Electrons  J1 j or J1 J2 Coupling  J1 l or J1 L2 Coupling (J1 K Coupling)  LS1 Coupling (LK Coupling)  Coupling Schemes and Term Symbols  Eigenvector Composition of Levels  Ground Levels and Ionization Energies for the Neutral Atoms  Zeeman Effect  Term Series, Quantum Defects, and Spectral-line Series  Sequences  Isoelectronic Sequence  Isoionic, Isonuclear, and Homologous Sequences  Spectral Wavelength Ranges, Dispersion of Air  Wavelength (Frequency) Standards  Spectral Lines: Selection Rules, Intensities, Transition Probabilities, Values, and Line Strengths  Emission Intensities (Transition Probabilities)  Absorption f values  Line Strengths  Relationships between A, f, and S  Relationships between Line and Multiplet Values  Relative Strengths for Lines of Multiplets in LS Coupling  Atomic Lifetimes  Regularities and Scaling  Transitions in Hydrogenic (One-Electron) Species  Systematic Trends and Regularities in Atoms and Ions with Two or More Electrons  Spectral Line Shapes, Widths, and Shifts  Doppler Broadening  Pressure Broadening  Spectral Continuum Radiation  Hydrogenic Species  Many-Electron Systems  Sources of Spectroscopic Data  References

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Online: February 1999   -   Last update: May 2007