Minima Hopping Guided Path Search: An Efficient Method for Finding Complex Chemical Reaction Pathways

摘要

The Minima Hopping global optimization method uses physically realizablemolecular dynamics moves in combination with an energy feedback that guaranteesthe escape from any potential energy funnel. For the purpose of findingreactions pathways, we argue that Minima Hopping is particularly suitable as aguide through the potential energy landscape and as a generator for pairs ofminima that can be used as input structures for methods capable of findingtransition states between two minima. For Lennard-Jones benchmark systems wecompared this Minima Hopping guided path search method to a known approach forthe exploration of potential energy landscapes that is based on deterministicmode-following. Although we used a stabilized mode-following technique thatreliably allows to follow distinct directions when escaping from a localminimum, we observed that Minima Hopping guided path search is far superior infinding lowest-barrier reaction pathways. We therefore suggest that MinimaHopping guided path search can be used as a simple and efficient way toidentify energetically low-lying chemical reaction pathways. Finally we appliedthe Minima Hopping guided path search approach to 75-atom and 102-atom LennardJones systems. For the 75-atom system we found pathways whose highest energiesare significantly lower than the highest energy along the previously publishedlowest-barrier pathway. Furthermore, many of these pathways contain a smallernumber of intermediate transition states than the previously publishlowest-barrier pathway. In case of the 102-atom system Minima Hopping guidedpath search found a previously unknown and energetically low-lying funnel.