Title: Einstein equation
Long Title: IUPAC Gold Book - Einstein equation
DOI: 10.1351/goldbook.ET06759
Status: current

Definition
In its most general form, the Einstein equation relates the atomic mobility \(b_{i}\) of a species \(i\) to the diffusion coefficient \(D_{i}\): i.e., \(D_{i}=k\ T\ b_{i}\).

Related Terms
- Einstein: https://goldbook.iupac.org//terms/view/E01914
- diffusion coefficient: https://goldbook.iupac.org//terms/view/D01719
- mobility: https://goldbook.iupac.org//terms/view/M03955

Source
- PAC, 1999, 71, 1307. 'Definitions of Terms for Diffusion in the Solid State' on page 1314 (https://doi.org/10.1351/pac199971071307)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/ET06759/html
- json: https://goldbook.iupac.org/terms/view/ET06759/json
- xml: https://goldbook.iupac.org/terms/view/ET06759/xml

Citation: Citation: 'Einstein equation' 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.ET06759
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Accessed: 2026-06-12T10:17:27+00:00