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Computational chemistry uses numerical models to predict or interpret chemical structure, energetics and dynamics. Electronic calculations may approximate the Schrödinger equation through Hartree-Fock theory or density functional theory; molecular simulations can instead evolve nuclei using an approximate potential.

A geometry optimization searches for a stationary point on a potential energy surface, while a vibration calculation examines its local curvature. These are different tasks: a converged numerical solution need not be an accurate physical prediction, and a stationary structure need not be the global energy minimum. Method, basis, environment and uncertainty therefore belong with a reported computed result.

Matthias Hofmann combined computational chemistry with NMR spectroscopy to resolve the solution structure of an arachno borane anion. Comparing calculated structures and NMR behaviour identified a fluxional structure and distinguished the lowest-energy form from an intermediate involved in rearrangement.^[ref]

Paul von Ragué Schleyer developed a short preparation of adamantane, a cage-shaped hydrocarbon, and became a major contributor to computational chemistry. His 1957 report illustrates how rearrangement reaction can turn a different carbon skeleton into a highly symmetrical cage.^[ref]