Term: curly arrows
https://doi.org/10.1351/goldbook.08160

Definition:
Symbols for depicting the flow of electrons in a chemical reaction or to generate additional resonance forms.

Notes:
1) The tail of the curly arrow shows where an electron pair originates, and the head of the curly arrow shows where the electron pair goes.
2) Single-headed curly arrows are used to depict the flow of unpaired electrons.

Example: [image]

Example: Array

Related Term: resonance forms (http://doi.org/10.1351/goldbook.08205).

Image: curly arrows (https://goldbook.iupac.org/img/inline/08160.jpg) 

Source: PAC, 2022, 94, 353. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 2021)' on page 395 (https://doi.org/10.1515/pac-2018-1010)

Citation: 'curly arrows' 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.08160

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