Cavity catalysis: modifying linear free-energy relationship under cooperative vibrational strong coupling. Issue 1 (8th December 2021)

• Record Type: Journal Article
• Authors: Lather, Jyoti; Thabassum, Ahammad N. K.; Singh, Jaibir; George, Jino
• Is Part Of: Chemical science. Volume 13:Issue 1(2022)
• Page Start: 195
• Page End: 202
• Publication Date: 2021-12-08
• Subjects: Chemistry -- Periodicals; 540.5
• DOI: 10.1039/d1sc04707h
• Languages: English
• ISSNs: 2041-6520

Abstract

Abstract : Cavity catalysis: vibrational strong coupling of solute and solvent molecules enhanced the rate of an esterification reaction. Hammett relation breaks under strong light-matter coupling conditions suggesting its potential applications in catalysis. Abstract : Here, we used an unconventional idea of cooperative vibrational strong coupling of solute and solvent molecules to enhance the rate of an esterification reaction. Different derivatives of p -nitrophenyl benzoate (solute) and isopropyl acetate (solvent) are cooperatively coupled to an infrared Fabry–Perot cavity mode. The apparent rates are increased by more than six times at the ON resonance condition, and the rate enhancement follows the lineshape of the vibrational envelope. Very interestingly, a strongly coupled system doesn't obey the Hammett relations. Thermodynamics suggests that the reaction mechanism remains intact for cavity and non-cavity conditions. Temperature-dependent experiments show an entropy-driven process for the coupled molecules. Vacuum field coupling decreases the free energy of activation by 2–5 kJ mol −1, supporting a catalysis process. The non-linear rate enhancement can be due to the reshuffling of the energy distribution between the substituents and the reaction center across the aromatic ring. These findings underline the non-equilibrium behavior of cavity catalysis.