| Autor: |
Rashid U; Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India., Medrano Sandonas L; Institute for Materials Science and Max Bergmann Center of Biomaterials, TU Dresden, 01062 Dresden, Germany., Chatir E; Université Grenoble Alpes, CNRS, DCM, UMR 5250, 38000 Grenoble, France., Ziani Z; LCC, CNRS, UPS, and INP Université de Toulouse, 31077 Toulouse, France., Sreelakshmi PA; Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India., Cobo S; Université Grenoble Alpes, CNRS, DCM, UMR 5250, 38000 Grenoble, France.; LCC, CNRS, UPS, and INP Université de Toulouse, 31077 Toulouse, France., Gutierrez R; Institute for Materials Science and Max Bergmann Center of Biomaterials, TU Dresden, 01062 Dresden, Germany., Cuniberti G; Institute for Materials Science and Max Bergmann Center of Biomaterials, TU Dresden, 01062 Dresden, Germany.; Dresden Center for Computational Materials Science (DCMS), TU Dresden, 01062 Dresden, Germany., Kaliginedi V; Department of Inorganic and Physical Chemistry, Indian Institute of Science, Bangalore 560012, India. |
| Abstrakt: |
Photoswitchable molecules with structural flexibility can exhibit a complex ground state potential energy landscape due to the accessibility of multiple metastable states at merely low energy barriers. However, conventional bulk analytical techniques are limited in their ability to probe these metastable ground states and their relative energies. This is partially due to the difficulty of inducing changes in small molecules in their ground state, as they do not respond to external stimuli, such as mechanical force, unless they are incorporated into larger polymer networks. This hinders the understanding of ground-state reactivity and the associated dynamics. In this study, we leverage the "perturb-probe" capability of the single molecular break junction technique to explore the ground state 6π electrocyclization of a dithienylethene (DTE) derivative, a process traditionally achieved through electro- or photochromism. Our findings reveal that this reaction can also be triggered by mechanical force and an oriented electric field at the single-molecule level via ground state dynamics. We demonstrated that external perturbations could control the ground state reaction dynamics and steer the reaction trajectories away from constraints imposed by typical excited state dynamics. This strategy will thus offer access to a whole new dimension of single molecular electromechanical conversions and extend our knowledge of the ground state potential energy surface available to molecules under external force fields. |
