Related Experiment Video
Updated: May 16, 2026
16:11
Thermochemical Studies of Ni(II) and Zn(II) Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Direct three-body dynamics govern ion-atom recombination and barrierless termolecular reactions
Rian Koots1, Marjan Mirahmadi2, Jesús Pérez-Ríos1
1Department of Physics and Astronomy, Stony Brook University, Stony Brook 11794, NY, USA. jesus.perezrios@stonybrook.edu.
Physical Chemistry Chemical Physics : PCCP
|May 14, 2026
Summary
Barrierless termolecular reactions are governed by direct three-body dynamics, not the Lindemann-Hinshelwood mechanism. This finding resolves long-standing discrepancies in chemical reaction theory.
Area of Science:
- Chemical Kinetics
- Physical Chemistry
- Theoretical Chemistry
Background:
- The Lindemann-Hinshelwood mechanism has explained termolecular reactions for over a century.
- This mechanism assumes sequential stabilization through bimolecular encounters.
- However, this model faces challenges with barrierless reactions.
Purpose of the Study:
- To investigate the fundamental dynamics of barrierless termolecular reactions.
- To challenge the prevailing Lindemann-Hinshelwood mechanism for these reactions.
- To establish a new mechanistic framework for barrierless termolecular reactions.
Main Methods:
- Utilized classical trajectory calculations.
- Employed hyperspherical coordinates for dynamic analysis.
- Focused on ion-atom recombination kinetics.
Main Results:
- Demonstrated that barrierless termolecular reactions are governed by direct three-body dynamics.
- Quantitatively reproduced experimental ion-atom recombination kinetics across a wide temperature range.
- Did not require intermediate complexes or steady-state assumptions.
Conclusions:
- The Lindemann-Hinshelwood mechanism is not universally applicable to termolecular reactions, especially barrierless ones.
- Direct three-body dynamics provide a more accurate framework for understanding these reactions.
- The findings have broad implications for atmospheric chemistry, plasma physics, and ultracold chemistry.
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