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elements.<br>Suitable for high-resolution color printing for desk or wall-chart display.<strong> </strong></p><p><a href="https://www.nist.gov/pml/fundamental-physical-constants"><strong>Physical Constants</strong></a></p><p>Contains values of the fundamental physical constants and a related bibliographic database.</p><p><a href="https://www.nist.gov/pml/atomic-spectroscopy-databases"><strong>Atomic Spectroscopy Data</strong></a></p><p>Contains databases for energy levels, wavelengths, radiative transition probabilities, and ionization energies for atoms and ions and related bibliographic databases.</p><p><a href="https://www.nist.gov/pml/molecular-spectroscopic-data"><strong>Molecular Spectroscopic Data</strong></a></p><p>Includes databases containing spectroscopic data for small molecules, hydrocarbons, and interstellar molecules. 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