Term: metallocenes
https://doi.org/10.1351/goldbook.M03865

Definition:
Organometallic coordination compounds in which one atom of a transition metal such as iron, ruthenium or osmium is bonded to and only to the face of two cyclopentadienyl [η5-(C5H5)] ligands which lie in parallel planes. The term should not be used for analogues having rings other than cyclopentadienyl as ligands. M03865.png

Related Terms:
1) coordination (http://doi.org/10.1351/goldbook.C01329).
2) ligands (http://doi.org/10.1351/goldbook.L03518).

Image: Not defined (https://goldbook.iupac.org/img/inline/M03865.png) 

Source: PAC, 1995, 67, 1307. 'Glossary of class names of organic compounds and reactivity intermediates based on structure (IUPAC Recommendations 1995)' on page 1349 (https://doi.org/10.1351/pac199567081307)

Citation: 'metallocenes' 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.M03865

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