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Title: Bowl breakout: Escaping the positive region when searching for saddle points

Abstract

We present a scheme improving the minimum-mode following method for finding first order saddle points by confining the displacements of atoms to the subset of those subject to the largest force. By doing so it is ensured that the displacement remains of a local character within regions where all eigenvalues of the Hessian matrix are positive. However, as soon as a region is entered where an eigenvalue turns negative all atoms are released to maintain the ability of determining concerted moves. Applying the proposed scheme reduces the required number of force calls for the determination of connected saddle points by a factor two or more compared to a free search. Furthermore, a wider distribution of the relevant low barrier saddle points is obtained. Finally, the dependency on the initial distortion and the applied maximal step size is reduced making minimum-mode guided searches both more robust and applicable.

Authors:
 [1];  [2];  [3]
  1. Faculty of Physical Sciences, University of Iceland VR-III, 107 Reykjavík (Iceland)
  2. (Switzerland)
  3. Integrated Systems Laboratory, ETH Zurich, 8092 Zurich (Switzerland)
Publication Date:
OSTI Identifier:
22308769
Resource Type:
Journal Article
Resource Relation:
Journal Name: Journal of Chemical Physics; Journal Volume: 141; Journal Issue: 2; Other Information: (c) 2014 AIP Publishing LLC; Country of input: International Atomic Energy Agency (IAEA)
Country of Publication:
United States
Language:
English
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ATOMS; COMPARATIVE EVALUATIONS; DIFFUSION BARRIERS; EIGENVALUES

Citation Formats

Pedersen, Andreas, Integrated Systems Laboratory, ETH Zurich, 8092 Zurich, and Luiser, Mathieu. Bowl breakout: Escaping the positive region when searching for saddle points. United States: N. p., 2014. Web. doi:10.1063/1.4885852.
Pedersen, Andreas, Integrated Systems Laboratory, ETH Zurich, 8092 Zurich, & Luiser, Mathieu. Bowl breakout: Escaping the positive region when searching for saddle points. United States. doi:10.1063/1.4885852.
Pedersen, Andreas, Integrated Systems Laboratory, ETH Zurich, 8092 Zurich, and Luiser, Mathieu. Mon . "Bowl breakout: Escaping the positive region when searching for saddle points". United States. doi:10.1063/1.4885852.
@article{osti_22308769,
title = {Bowl breakout: Escaping the positive region when searching for saddle points},
author = {Pedersen, Andreas and Integrated Systems Laboratory, ETH Zurich, 8092 Zurich and Luiser, Mathieu},
abstractNote = {We present a scheme improving the minimum-mode following method for finding first order saddle points by confining the displacements of atoms to the subset of those subject to the largest force. By doing so it is ensured that the displacement remains of a local character within regions where all eigenvalues of the Hessian matrix are positive. However, as soon as a region is entered where an eigenvalue turns negative all atoms are released to maintain the ability of determining concerted moves. Applying the proposed scheme reduces the required number of force calls for the determination of connected saddle points by a factor two or more compared to a free search. Furthermore, a wider distribution of the relevant low barrier saddle points is obtained. Finally, the dependency on the initial distortion and the applied maximal step size is reduced making minimum-mode guided searches both more robust and applicable.},
doi = {10.1063/1.4885852},
journal = {Journal of Chemical Physics},
number = 2,
volume = 141,
place = {United States},
year = {Mon Jul 14 00:00:00 EDT 2014},
month = {Mon Jul 14 00:00:00 EDT 2014}
}
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