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arXiv · 2512.22572

Variational quantum eigensolver for chemical molecules

Luca Ion·Adam Smith
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Abstract

Solving interacting multi-particle systems is a central challenge in quantum chemistry and condensed matter physics. In this work, we investigate the computation of ground states and ground-state energies for the He-H+ and H2O molecules using quantum computing techniques. We employ the variational quantum eigensolver (VQE), implemented both on a quantum computer simulator and on an IBM quantum device. The resulting energies are benchmarked against exact ground-state energies obtained via classical methods. Simulations of the H2O molecule were performed on Nottingham's High Performance Computing (HPC) facilities.

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Luca Ion, Adam Smith. 2025-12-27. Variational quantum eigensolver for chemical molecules. https://arxiv.org/abs/2512.22572

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