Term: normal region (for electron transfer)
https://doi.org/10.1351/goldbook.N04215

Definition:
Region for which the rate constants increase with increasing exergonicity of the reaction in plots relating rate constants for electron transfer, or quantities related to it, with the standard Gibbs energy for the reaction (ΔET.Go). This region is predicted by the Marcus theory for outer-sphere electron transfer for the case of -ΔETGo ≤ λ in the Marcus equation.

Related Terms:
1) electron transfer (http://doi.org/10.1351/goldbook.E02011).
2) outer-sphere electron transfer (http://doi.org/10.1351/goldbook.O04351).

Source: PAC, 2007, 79, 293. 'Glossary of terms used in photochemistry, 3rd edition (IUPAC Recommendations 2006)' on page 375 (https://doi.org/10.1351/pac200779030293)

Citation: 'normal region (for 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.N04215

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