Term: electron density
https://doi.org/10.1351/goldbook.E01986

Definition:
If P x y z d x d y d z is the probability of finding an electron in the volume element dx dy dz at the point of a molecular entity with coordinates x , y , z, then P x y z is the electron density at this point. For many purposes (e.g. X-ray scattering, forces on atoms) the system behaves exactly as if the electrons were spread out into a continuously distributed charge. The term has frequently been wrongly applied to negative charge population.

Related Terms:
1) charge density (http://doi.org/10.1351/goldbook.C00988).
2) probability (http://doi.org/10.1351/goldbook.P04855).
3) scattering (http://doi.org/10.1351/goldbook.S05487).
4) charge population (http://doi.org/10.1351/goldbook.C00997).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1110 (https://doi.org/10.1351/pac199466051077)

Citation: 'electron density' 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.E01986

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