Quantum Coherence-Controlled Chemical Reactions

University Of Chicago, Chicago IL

Investigators

Abstract

Many industrially important chemical production processes require significant energy input to drive the chemical reactions. When this power is provided by heating the chemical reactants, undesired side reactions can take place reducing the process yield and potentially posing a safety risk. While much more controlled power inputs exist, sources such as lasers have fixed wavelengths and so are limited to use in only a handful of reactions. In this work, a new approach is proposed to use quantum mechanical principles to design chemical reactors that can redirect random chemical reactant molecular motions to promote a specific chemical reaction. Much like a catalyst, this would result in greater chemical reactor efficiency. The unique combination of chemistry and quantum mechanics proposed would lead to a new approach for chemical synthesis by design. This project will leverage a close collaboration between the University of Chicago and Argonne National Laboratory for the successful implementation of this multidisciplinary study. This research will also contribute to the education and mentoring of graduate students and postdoctoral researchers involved through their training and research during the project. Outreach programs developed during this project will foster the integration of research and teaching, as well as the participation of underrepresented groups. Electronic ground state reactions rely on the excitation of specific vibrational motions along the reaction coordinates. However, selective excitation of one specific vibrational mode of a chemical bond while leaving the others intact is challenging. The principle intellectual merit of the proposed work is to address this long-standing challenge faced by the chemical synthesis community and develop a reaction control mechanism that not only allows bond-selective excitation of chemical reactions, but also the modulation of reaction potential energy surfaces. The quantum coherence approach developed here would enable the tuning of a particular reaction channel’s potential barrier for its reaction rate acceleration or deceleration. During the first stage of the project, we will focus on understanding the influence of the quantum coherence effects on several key reaction parameters, including the reaction rate, selectivity, and yield. In the second stage, we aim to optimize the reaction control mechanism and adapt it to potential scale-up applications. Two important chemical reactions will be studied in this work and will serve as representatives of a wide range of potential applications. This award reflects NSF's statutory mission and has been deemed worthy of support through evaluation using the Foundation's intellectual merit and broader impacts review criteria.