Term: attractive potential-energy surface
https://doi.org/10.1351/goldbook.A00519

Definition:
A potential-energy (reaction) surface for a process A + B–C in which the initial descent of the system into the product valley is associated with a substantial decrease in the A–B distance and with little separation between the products A–B and C. In terms of a potential-energy profile, the energy barrier occurs in the early stage of the reaction path. Attractive surfaces are also called early-downhill surfaces, and the barrier in such a surface is called a Type-I barrier.

Related Terms:
1) potential-energy (reaction) surface (http://doi.org/10.1351/goldbook.P04780).
2) potential-energy profile (http://doi.org/10.1351/goldbook.P04779).
3) reaction path (http://doi.org/10.1351/goldbook.R05174).

Source: PAC, 1996, 68, 149. 'A glossary of terms used in chemical kinetics, including reaction dynamics (IUPAC Recommendations 1996)' on page 153 (https://doi.org/10.1351/pac199668010149)

Citation: 'attractive potential-energy surface' 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.A00519

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