Measuring orbital interaction using quantum information theory

J. Rissler; R. M. Noack; S. R. White

doi:10.1016/j.chemphys.2005.10.018

paper

Measuring orbital interaction using quantum information theory

arXiv:cond-mat/0508524 · doi:10.1016/j.chemphys.2005.10.018

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.

26 pages, 14 figures