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Simulation of unimolecular fluoromethane dissociation on a quantum computer using the cascaded variational quantum eigensolver algorithm

Gloria Bazargan*, John P. T. Stenger, and Daniel Gunlycke

  • *Contact author: gloria.bazargan.civ@us.navy.mil
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APS Open Sci. 1, 000127 – Published 8 September, 2026

DOI: https://doi.org/10.1103/1ljr-8zrf

Abstract

Simulating chemical reactions on quantum computers has the potential to offer insight that cannot be gained practically from conventional quantum-chemical approaches on classical computers. This is because quantum computing provides a platform for efficient, high-level electronic structure calculations that approach the full configuration interaction (FCI) limit. Herein, we apply the cascaded variational quantum eigensolver (CVQE) algorithm to simulate the unimolecular dissociation of fluoromethane (CH3F) by two pathways: (1) CH3F→CH2+HF and (2) CH3F→CHF+H2. We compare the results of CVQE calculations performed on the ibm_torino quantum computer to configuration interaction benchmarks run on a classical computer. Our results demonstrate that CVQE predicts lower energies than classical configuration interaction with singles, doubles, and triples for all geometries considered, and achieves chemical accuracy relative to FCI in nearly all cases. This suggests that quantum computing with CVQE can provide high-level electronic structure information for chemical reactions and other cases that require the simulation of multiple geometries.

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Outline

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APS Open Sci. 1, 000127– Published 8 September, 2026
Vol. 1
  • Received 27 May 2026
  • Revised 16 July 2026
  • Accepted 26 August 2026
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Published by the American Physical Society under the terms of the Creative Commons Attribution 4.0 International license. Further distribution of this work must maintain attribution to the author(s) and the published article's title, journal citation, and DOI.

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