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Measuring orbital interaction using quantum information theory

J. Rissler·R. M. Noack·S. R. White
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Abstract

Quantum information theory gives rise to a straightforward definition of the interaction of electrons $I_{p,q}$ in two orbitals $p$, $q$ for a given many-body wave function. A convenient way to calculate the von Neumann entropies needed is presented in this work, and the orbital interaction $I_{p,q}$ is successfully tested for different types of chemical bonds. As an example of an application of $I_{p,q}$ beyond the interpretation of wave functions, $I_{p,q}$ is then used to investigate the ordering problem in the density-matrix renormalization group.

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J. Rissler, R. M. Noack, S. R. White. 2005-08-22. Measuring orbital interaction using quantum information theory. https://doi.org/10.1016/j.chemphys.2005.10.018

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