IUPAC > Gold Book > alphabetical index > W > wavenumber, σ, ν ˜


wavenumber, σ, ν ˜

The reciprocal of the wavelength, λ, or the number of waves per unit length along the direction of propagation. The SI unit is m −1, but a commonly used unit is cm −1. Symbols ν ˜ in a vacuum, σ in a medium.
PAC, 1996, 68, 2223 (Glossary of terms used in photochemistry (IUPAC Recommendations 1996)) on page 2283
PAC, 1985, 57, 105 (Names, symbols, definitions and units of quantities in optical spectroscopy (Recommendations 1984)) on page 109
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IUPAC. Compendium of Chemical Terminology, 2nd ed. (the "Gold Book"). Compiled by A. D. McNaught and A. Wilkinson. Blackwell Scientific Publications, Oxford (1997). XML on-line corrected version: http://goldbook.iupac.org (2006-) created by M. Nic, J. Jirat, B. Kosata; updates compiled by A. Jenkins. ISBN 0-9678550-9-8. doi:10.1351/goldbook.
Last update: 2014-02-24; version: 2.3.3.
DOI of this term: doi:10.1351/goldbook.W06664.
Original PDF version: http://www.iupac.org/goldbook/W06664.pdf. The PDF version is out of date and is provided for reference purposes only. For some entries, the PDF version may be unavailable.
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