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Energy Barrier Scalings in Driven Systems

Craig E. Maloney·Daniel J. Lacks
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Abstract

Energy landscape mappings are performed for two different molecular systems under mechanical loads. Barrier heights are observed to scale as $ΔU\simδ^{3/2}$, where $δ$ is a residual load. Catastrophe theory predicts that this scaling should arise for vanishing $δ$, however, this region is irrelevant in physical processes at finite temperature because thermal fluctuations cause the system to cross over the barrier before reaching the small $δ$ regime. Surprisingly, we find that the $ΔU\simδ^{3/2}$ scaling is valid far beyond the vanishing $δ$ regime described by catastrophe theory. This scaling will therefore be relevant at finite temperatures, and can be the basis for corrections to standard rate theoretic approaches.

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Craig E. Maloney, Daniel J. Lacks. 2005-08-22. Energy Barrier Scalings in Driven Systems. https://doi.org/10.1103/physreve.73.061106

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