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Barnes Update Applied in the Gauss-Newton Method: An Improved Algorithm to Locate Bond Breaking Points.
Josep Maria Bofill1,2, Rosendo Valero2,3, Jordi Ribas-Ariño2,3
1Departament de Química Inorgànica i Orgànica, Secció de Química Orgànica, Universitat de Barcelona, Martí i Franquès 1, 08028 Barcelona, Spain.
Journal of Chemical Theory and Computation
|January 19, 2021
Summary
This study introduces a new algorithm to find critical bond-breaking points in mechanochemical reactions. The method efficiently identifies how to apply force to initiate chemical reactions, aiding mechanochemistry research.
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Area of Science:
- Computational Chemistry
- Mechanochemistry
- Chemical Physics
Background:
- Mechanochemical reactions are initiated by mechanical energy, often modeled as perturbations to potential energy surfaces (PES).
- Optimal bond breaking points (BBPs) are critical on the PES, where the Hessian matrix's zero eigenvector aligns with the gradient, indicating optimal force application.
Purpose of the Study:
- To develop a novel, efficient algorithm for locating optimal bond breaking points (BBPs) in molecular systems.
- To improve upon existing methods for identifying critical points in mechanochemical reactions.
Main Methods:
- The proposed algorithm combines the Gauss-Newton method with the Barnes update for handling nonsymmetric Jacobian matrices.
- This approach is presented as an improvement over the Broyden update for BBP localization.
Main Results:
- The new algorithm's efficiency is demonstrated on a multidimensional model potential energy surface (PES).
- The method's effectiveness is further validated using two medium-sized molecular systems relevant to enzymatic catalysis and mechanochemistry.
Conclusions:
- The developed Gauss-Newton-based algorithm provides an efficient means to locate optimal bond breaking points (BBPs).
- This method facilitates the understanding and harnessing of tensile forces for inducing mechanochemical reactions, transforming them into barrierless processes.