Elucidating Reaction Mechanisms on Quantum Computers

TL;DR

This paper demonstrates how quantum computers can be used to elucidate complex chemical reaction mechanisms, such as biological nitrogen fixation, by augmenting classical simulations and enabling intractable calculations.

Contribution

It introduces a method for using quantum computers to study reaction mechanisms, providing detailed resource estimates and showing feasibility with small quantum computers.

Findings

Quantum computers can significantly improve accuracy of chemical simulations.

Necessary computations are feasible within reasonable time on small quantum computers.

Quantum error correction overhead is manageable for these applications.

Abstract

We show how a quantum computer can be employed to elucidate reaction mechanisms in complex chemical systems, using the open problem of biological nitrogen fixation in nitrogenase as an example. We discuss how quantum computers can augment classical-computer simulations for such problems, to significantly increase their accuracy and enable hitherto intractable simulations. Detailed resource estimates show that, even when taking into account the substantial overhead of quantum error correction, and the need to compile into discrete gate sets, the necessary computations can be performed in reasonable time on small quantum computers. This demonstrates that quantum computers will realistically be able to tackle important problems in chemistry that are both scientifically and economically significant.