Term: inner-sphere electron transfer
https://doi.org/10.1351/goldbook.I03052

Definition:
Historically an electron transfer between two metal centres sharing a ligand or atom in their respective coordination shells. The definition has more recently been extended to any situation in which the interaction between the donor and acceptor centres in the transition state is significant (> 20 kJ mol-1).

Related Terms:
1) outer-sphere electron transfer (http://doi.org/10.1351/goldbook.O04351).
2) electron transfer (http://doi.org/10.1351/goldbook.E02011).
3) coordination (http://doi.org/10.1351/goldbook.C01329).
4) transition state (http://doi.org/10.1351/goldbook.T06468).

Source: PAC, 1994, 66, 1077. 'Glossary of terms used in physical organic chemistry (IUPAC Recommendations 1994)' on page 1125 (https://doi.org/10.1351/pac199466051077)

Citation: 'inner-sphere electron transfer' 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.I03052

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