Term: monolayer
https://doi.org/10.1351/goldbook.M04015

Definition:
A single, closely packed layer of atoms or molecules. The term floating monolayer is used for certain spread monolayers or films which are in the condensed — often solid — state. The term Langmuir monolayer has recently been coined for spread monolayers. This usage is not recommended.

Related Terms:
1) layer (http://doi.org/10.1351/goldbook.L03488).
2) films (http://doi.org/10.1351/goldbook.F02366).
3) langmuir monolayer (http://doi.org/10.1351/goldbook.L03452).

Source: PAC, 1994, 66, 1667. 'Thin films including layers: terminology in relation to their preparation and characterization (IUPAC Recommendations 1994)' on page 1672 (https://doi.org/10.1351/pac199466081667)

Citation: 'monolayer' 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.M04015

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