Term: Lewis acid
https://doi.org/10.1351/goldbook.L03508

Definition:
A molecular entity (and the corresponding chemical species) that is an electron-pair acceptor and therefore able to react with a Lewis base to form a Lewis adduct, by sharing the electron pair furnished by the Lewis base. For example: L03508.png

Related Terms:
1) coordination (http://doi.org/10.1351/goldbook.C01329).
2) dipolar bond (http://doi.org/10.1351/goldbook.D01752).
3) molecular entity (http://doi.org/10.1351/goldbook.M03986).
4) chemical species (http://doi.org/10.1351/goldbook.CT01038).
5) lewis base (http://doi.org/10.1351/goldbook.L03511).
6) lewis adduct (http://doi.org/10.1351/goldbook.L03510).
7) electron-pair acceptor (http://doi.org/10.1351/goldbook.E02003).

Image: Not defined (https://goldbook.iupac.org/img/inline/L03508.png) 

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1135 (https://doi.org/10.1351/pac199466051077)

Citation: 'Lewis acid' 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.L03508

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