Term: projection formula
https://doi.org/10.1351/goldbook.P04873

Definition:
A formal two-dimensional representation of a three-dimensional molecular structure obtained by projection of bonds (symbolized as lines) onto a plane with or without the designation of the positions of relevant atoms by their chemical symbols. A projection formula which indicates the spatial arrangement of bonds is called a stereochemical formula or stereoformula. Examples of stereoformulae are Fischer projection, Newman projection, sawhorse projection, wedge projection and zig-zag projection.

Related Terms:
1) perspective formula (http://doi.org/10.1351/goldbook.P04517).
2) stereochemical formula (http://doi.org/10.1351/goldbook.S05974).
3) fischer projection (http://doi.org/10.1351/goldbook.F02391).
4) newman projection (http://doi.org/10.1351/goldbook.N04134).
5) sawhorse projection (http://doi.org/10.1351/goldbook.S05480).
6) wedge projection (http://doi.org/10.1351/goldbook.W06667).
7) zig-zag projection (http://doi.org/10.1351/goldbook.Z06747).

Source: PAC, 1996, 68, 2193. 'Basic terminology of stereochemistry (IUPAC Recommendations 1996)' on page 2214 (https://doi.org/10.1351/pac199668122193)

Citation: 'projection formula' 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.P04873

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