Term: excimer
https://doi.org/10.1351/goldbook.E02242

Definition:
An electronically excited dimer, 'non-bonding' in the ground state. For example, a complex formed by the interaction of an excited molecular entity with a ground state partner of the same structure.

Related Terms:
1) exciplex (http://doi.org/10.1351/goldbook.E02246).
2) ground state (http://doi.org/10.1351/goldbook.G02704).
3) molecular entity (http://doi.org/10.1351/goldbook.M03986).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1114 (https://doi.org/10.1351/pac199466051077)

Citation: 'excimer' 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.E02242

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