Submolecular-scale control of phototautomerization

Anna Rosławska; Katharina Kaiser; Michelangelo Romeo; Eloïse Devaux; Fabrice Scheurer; Stéphane Berciaud; Tomáš Neuman; Guillaume Schull

arXiv · 2305.13157

Submolecular-scale control of phototautomerization

Anna Rosławska·Katharina Kaiser·Michelangelo Romeo·Eloïse Devaux·Fabrice Scheurer·Stéphane Berciaud·Tomáš Neuman·Guillaume Schull

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Abstract

Many natural and artificial reactions including photosynthesis or photopolymerization are initiated by stimulating organic molecules into an excited state, which enables new reaction paths. Controlling light-matter interaction can influence this key concept of photochemistry, however, it remained a challenge to apply this strategy to control photochemical reactions at the atomic scale. Here, we profit from the extreme confinement of the electromagnetic field at the apex of a scanning tunneling microscope (STM) tip to drive and control the rate of a free-base phthalocyanine phototautomerization with submolecular precision. By tuning the laser excitation wavelength and choosing the STM tip position, we control the phototautomerization rate and the relative tautomer population. This sub-molecular optical control can be used to study any other photochemical processes.

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Anna Rosławska, Katharina Kaiser, Michelangelo Romeo, Eloïse Devaux, Fabrice Scheurer, Stéphane Berciaud, Tomáš Neuman, Guillaume Schull. 2023-05-22. Submolecular-scale control of phototautomerization. https://arxiv.org/abs/2305.13157

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