Term: metal to metal charge transfer (MMCT) transition
https://doi.org/10.1351/goldbook.M03869

Definition:
An electronic transition of a bi- or poly-nuclear metal complex that corresponds to excitation populating an electronic state in which considerable electron transfer between two metal centres has occurred.

Related Terms:
1) intervalence charge transfer (http://doi.org/10.1351/goldbook.I03125).
2) electronic state (http://doi.org/10.1351/goldbook.ET07026).
3) electron transfer (http://doi.org/10.1351/goldbook.E02011).

Source: PAC, 1996, 68, 2223. 'Glossary of terms used in photochemistry (IUPAC Recommendations 1996)' on page 2254 (https://doi.org/10.1351/pac199668122223)

Citation: 'metal to metal charge transfer (MMCT) transition' 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.M03869

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