Term: transient phase (induction period)
https://doi.org/10.1351/goldbook.T06450

Definition:
This expression relates to the period of time that elapses prior to the establishment of a steady state. Initially the concentration of a reactive intermediate is zero, and it rises to the steady-state concentration during the transient phase.

Related Terms:
1) steady state (http://doi.org/10.1351/goldbook.S05962).

Source: PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 189 (https://doi.org/10.1351/pac199668010149)

Citation: 'transient phase (induction period)' 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.T06450

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