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arXiv · 1308.6538

Specific chemical reactivities of spatially separated 3-aminophenol conformers with cold Ca$^+$ ions

Yuan-Pin Chang·Karol Długołęcki·Jochen Küpper·Daniel Rösch·Dieter Wild·Stefan Willitsch
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Abstract

Many molecules exhibit multiple rotational isomers (conformers) that interconvert thermally and are difficult to isolate. Consequently, a precise characterization of their role in chemical reactions has proven challenging. We have probed the reactivity of specific conformers using an experimental technique based on their spatial separation in a molecular beam by electrostatic deflection. The separated conformers react with a target of Coulomb-crystallized ions in a trap. In the reaction of Ca$^+$ with 3-aminophenol, we find a twofold larger rate constant for the \textit{cis}- compared to the \textit{trans}-conformer (differentiated by the O-H bond orientation). This result is explained by conformer-specific differences in the long-range ion-molecule interaction potentials. Our approach demonstrates the possibility of controlling reactivity through selection of conformational states.

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Yuan-Pin Chang, Karol Długołęcki, Jochen Küpper, Daniel Rösch, Dieter Wild, Stefan Willitsch. 2013-08-29. Specific chemical reactivities of spatially separated 3-aminophenol conformers with cold Ca$^+$ ions. https://doi.org/10.1126/science.1242271

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