Title: wave vector
Long Title: IUPAC Gold Book - wave vector
DOI: 10.1351/goldbook.09441
Status: current

Definition
Vector in reciprocal space describing the direction of propagation of X-rays and equal in magnitude to \(2\uppi/\lambda\), where \(\lambda\) is the wavelength of the X-rays.

Note
In different fields of study, the wave vector is taken as \(2\uppi/\lambda\) or as \(1/\lambda\). In X-ray reflectometry the former is usually used.

Source
- PAC, 2020, 92, 1781. 'Glossary of methods and terms used in surface chemical analysis (IUPAC Recommendations 2020)' on page 1849 (https://doi.org/10.1515/pac-2019-0404)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/09441/html
- json: https://goldbook.iupac.org/terms/view/09441/json
- xml: https://goldbook.iupac.org/terms/view/09441/xml

Citation: Citation: 'wave vector' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. 10.1351/goldbook.09441
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Accessed: 2026-04-18T12:44:02+00:00