Ground-State Chemical Reactivity under Vibrational Coupling to the Vacuum Electromagnetic Field

Angew Chem Int Ed Engl. 2016 Sep 12;55(38):11462-6. doi: 10.1002/anie.201605504. Epub 2016 Aug 16.


The ground-state deprotection of a simple alkynylsilane is studied under vibrational strong coupling to the zero-point fluctuations, or vacuum electromagnetic field, of a resonant IR microfluidic cavity. The reaction rate decreased by a factor of up to 5.5 when the Si-C vibrational stretching modes of the reactant were strongly coupled. The relative change in the reaction rate under strong coupling depends on the Rabi splitting energy. Product analysis by GC-MS confirmed the kinetic results. Temperature dependence shows that the activation enthalpy and entropy change significantly, suggesting that the transition state is modified from an associative to a dissociative type. These findings show that vibrational strong coupling provides a powerful approach for modifying and controlling chemical landscapes and for understanding reaction mechanisms.

Keywords: IR spectroscopy; kinetics; strong coupling; thermodynamics; vibrations.

Publication types

  • Research Support, Non-U.S. Gov't