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Curvature-weighted nudged elastic band method using the Riemann curvature
Yuki Mitsuta1,2, Toshio Asada1,2
1Graduate School of Science, Osaka Metropolitan University, Osaka, Japan.
Journal of Computational Chemistry
|November 16, 2022
Summary
The curvature weighted nudged elastic band (CW-NEB) method improves reaction path calculations by accounting for curve complexity. This new approach, CW-NEB, converges faster for bent reaction paths.
Area of Science:
- Computational Chemistry
- Reaction Mechanism Studies
- Chemical Kinetics
Background:
- The nudged elastic band (NEB) method is standard for determining reaction paths (RPs) using discrete intermediate structures ('images').
- NEB calculations can fail to converge for RPs with significant curvature, requiring more images for complex paths.
- RP curvature is a critical factor influencing the efficiency and convergence of NEB simulations.
Purpose of the Study:
- To introduce a novel method for calculating the curvature of reaction paths.
- To develop a curvature-weighted NEB (CW-NEB) method that adjusts spring constants based on RP curvature.
- To propose an enhanced CW-NEB method incorporating the climbing image (CI) technique (CW-CI-NEB).
Main Methods:
- Development of a new algorithm to quantify reaction path curvature.
- Implementation of the curvature weighted NEB (CW-NEB) method, weighting spring constants by calculated curvature.
- Integration of CW-NEB with the climbing image (CI) method to form CW-CI-NEB.
Main Results:
- The proposed CW-NEB and CW-CI-NEB methods effectively handle the curvature of reaction paths.
- Calculations using the CW-CI-NEB method for an ene-reaction demonstrated faster convergence compared to standard CI-NEB.
- The CW-CI-NEB method showed improved performance by addressing the bending of RPs.
Conclusions:
- The CW-NEB method, particularly with the climbing image technique, offers a significant improvement for NEB calculations.
- This approach enhances convergence efficiency for reaction paths with complex geometries.
- The CW-CI-NEB method provides a more robust and efficient tool for exploring reaction mechanisms in computational chemistry.
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