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European Journal of Physics

A first exercise in quantum computing for molecular chemistry: the hydrogen molecule cation

Jed Brody, Shane Berhoff, Dixie Rose Baronofsky

Published Sep 3, 2026• 0 citations
Publisher

Abstract

Abstract Chemical simulation is expected to be one of the first practical applications of real quantum computers. Therefore, curricular materials should be developed to teach students the fundamentals of this very important topic. Even the simplest molecule, diatomic hydrogen, is tremendously complicated to simulate with a quantum computer. Much of the complexity is due to the interaction of the two electrons. As a first warm-up exercise in quantum computing for chemistry, we show how to simulate the hydrogen molecule cation, which has only one electron.

DOI
10.1088/1361-6404/aea272

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Abstract Chemical simulation is expected to be one of the first practical applications of real quantum computers. Therefore, curricular materials should be developed to teach students the fundamentals of this very important topic. Even the simplest molecule, diatomic hydrogen, is tremendously complicated to simulate with a quantum computer. Much of the complexity is due to the interaction of the two electrons. As a first warm-up exercise in quantum computing for chemistry, we show how to simulate the hydrogen molecule cation, which has only one electron.
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