Term: threshold energy, \(E_{0}\)
https://doi.org/10.1351/goldbook.T06366

Definition:
Potential energy gap between reactants and the transition state, sometimes involving the zero point energies, but usually not.

Related Terms:
1) critical energy (http://doi.org/10.1351/goldbook.C01393).
2) reactants (http://doi.org/10.1351/goldbook.R05163).
3) transition state (http://doi.org/10.1351/goldbook.T06468).

Source: Green Book, 2nd ed., p. 56 (https://goldbook.iupac.org/files/pdf/green_book_2ed.pdf)

Citation: 'threshold energy, \(E_{0}\)' 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.T06366

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