Term: elementary charge, \(e\)
https://doi.org/10.1351/goldbook.E02032

Definition:
The elementary charge, \(e\), is one of seven fixed constants defining the International System of Units, the SI, with \(e = 1.602\ 176\ 634\ \times 10^{-19}\ \text{C}\). The elementary charge \(e\) corresponds to a coupling strength of the electromagnetic force via the fine-structure constant and is considered as a fundamental constant of nature.

Source: BIPM, The International System of Units, SI Brochure, 9th ed. (2019), p. 127ff (https://www.bipm.org/en/publications/si-brochure/)

Citation: 'elementary charge, \(e\)' in IUPAC Compendium of Chemical Terminology, 5th ed. International Union of Pure and Applied Chemistry; 2025. Online version 5.0.0, 2025. https://doi.org/10.1351/goldbook.E02032

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