Least-Action Tunneling Transmission Coefficient for Polyatomic Reactions
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Updated: Mar 29, 2026

Thermochemical Studies of NiII and ZnII Ternary Complexes Using Ion Mobility-Mass Spectrometry
Published on: June 8, 2022
Rubén Meana-Pañeda1, Donald G Truhlar1, Antonio Fernández-Ramos1
1Department of Physical Chemistry, Faculty of Chemistry, University of Santiago de Compostela, 15782 Santiago de Compostela, Spain, and Department of Chemistry and Supercomputing Institute, University of Minnesota, 207 Pleasant Street S. E., Minneapolis, Minnesota 55455-0431.
Abstract:
We present a new least-action variational approximation for tunneling in polyatomic reactions based on the procedure developed by Garrett and Truhlar for atom-diatom reactions. (63) The method calculates the semiclassical ground-state tunneling probability at every tunneling energy by minimizing the value of imaginary action integral along a family of paths ranging from the minimum energy path to the straight path. The method is illustrated by applications to two hydrogen-atom abstraction reactions from methane using analytical potential energy surfaces.
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