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Updated: Jul 24, 2026

Spatial Separation of Molecular Conformers and Clusters
Published on: January 9, 2014
A family of intracules, a conjecture and the electron correlation problem
Peter M W Gill1, Deborah L Crittenden, Darragh P O'Neill
1Research School of Chemistry, Australian National University, ACT 0200, Australia. peter.gill@anu.edu.au
Abstract:
We present a radical approach to the calculation of electron correlation energies. Unlike conventional methods based on Hartree-Fock or density functional theory, it is based on the two-electron phase-space information in the Omega intracule, a three-dimensional function derived from the Wigner distribution. Our formula for the correlation energy is isomorphic to the Hartree-Fock energy expression but requires a new type of four-index integral. Preliminary results, obtained using a model that is based on the known correlation energies of small atoms, are encouraging.
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