Orbital resolution of molecular information channels and stockholder atoms

Abstract

Within the orbital description of the electronic structure of molecules the variational principles of the entropy deficiency and the entropy/information descriptors of the system communication channel are used to establish the orbital-representability (orthonormality) requirements in terms of the relevant conditional probabilities from the superposition principle of quantum mechanics. The orbital resolution of the Hirshfeld (stockholder) partition of the molecular electron density into the unbiased densities of bonded atoms is derived from the global and local principles of the maximum information-similarity between atoms-in-molecules and the free-atoms of the promolecule formulated in terms of the conditional probabilities of the (localized) atomic orbitals of constituent atoms. It is demonstrated that the universal (orbital- and atom-independent) local enhancement factors, which determine the unbiased orbital densities in such a division scheme, are the same as those characterizing the original (atom-condensed) partition of Hirshfeld. The orbital densities corresponding to these polarized atomic orbitals reproduce the overall densities of stockholder atoms and generate the effective orbital occupation numbers of bonded atoms in the molecular valence state.