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Results

The springs should distribute the images evenly along the NEB path during the optimisation, and the choice of $k_{spr}$ must be made at the beginning of each run. It has been suggested by Jónsson and coworkers that since the action of the springs is only felt along the path the value of the spring constant is not critical as long as it is not zero [27]. If $k_{spr}$ is set to zero then sensible behaviour occurs for the first several tens of iterations only; even though $\gtpar$ is projected out, $\bft$ fluctuates and further optimisation will eventually result in the majority of images gradually sliding down to local minima [27].

Subsections

Slow-response Quenched Velocity Verlet
Choice of the Force Constant
Comparison of SQVV and L-BFGS Minimisers for the MB Surface
Doubly Nudged Elastic Bands
Comparison of the DNEB/L-BFGS and DNEB/SQVV Methods for Permutational Isomerisations of LJ
A Revised Connection Algorithm
Applications to Isomerisation of LJ $_{38}$ and LJ $_{75}$
A Dijkstra-based Selector
Applications to Tryptophan Zippers

Semen A Trygubenko 2006-04-10