Energy Barrier Scalings in Driven Systems

Abstract

Energy landscape mappings are performed for two different molecular systems under mechanical loads. Barrier heights are observed to scale as $\Delta U\sim {\delta }^{3/2}$, where $\delta$ is a residual load. Catastrophe theory predicts that this scaling should arise for vanishing $\delta$, 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 $\delta$ regime. Surprisingly, we find that the $\Delta U\sim {\delta }^{3/2}$ scaling is valid far beyond the vanishing $\delta$ 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.

4 pages; 5 figures