Title: Hartree energy
Long Title: IUPAC Gold Book - Hartree energy
DOI: 10.1351/goldbook.H02748
Status: current
Index: constant

Definition
Atomic fundamental physical constant used as atomic unit of energy: \(E_{\rm{h}}=\frac{\mathrm{\hslash }^{2}}{m_{\rm{e}}\ a_{0}^{2}} = 4.359\ 7482(26)\times 10^{-18}\ \rm{J}\), where \(\mathrm{\hslash}\) is the Planck constant divided by \(2\ \pi \), \(m_{\rm{e}}\) the electron rest mass and \(a_{0}\) the Bohr radius.

Related Terms
- Bohr radius: https://goldbook.iupac.org//terms/view/B00693
- Planck constant: https://goldbook.iupac.org//terms/view/P04685
- atomic unit: https://goldbook.iupac.org//terms/view/A00504
- electron rest mass: https://goldbook.iupac.org//terms/view/E02008

Source
- CODATA Bull. 1986, 63, 1 (https://doi.org/10.6028/jres.092.010)

Other Outputs
- html: https://goldbook.iupac.org/terms/view/H02748/html
- json: https://goldbook.iupac.org/terms/view/H02748/json
- xml: https://goldbook.iupac.org/terms/view/H02748/xml

Citation: Citation: 'Hartree energy' 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.H02748
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Accessed: 2026-04-20T12:43:29+00:00