Atomic resolution of bond descriptors in the two-orbital model

Abstract

The probability-resolution scheme for partitioning the molecular bond-multiplicities into atomic contributions, suggested by the ‘partial’ atomic channels of the Communication Theory of the chemical bond, is applied to the simplest two-orbital model of a diatomic molecule. It offers a unique perspective upon a degree of the atom involvement in the covalent and ionic interactions with its molecular environment. The row channels generate the atomic contributions to the molecular bond-multiplicity and its covalent/ionic composition, while the atomic column channels give rise to the valence indices of bonded atoms, which reflect their promoted states in a molecule. Plots of the entropy/information bond indicators of atomic partial communication channels are generated over the whole range of the probability of finding an electron on the specified atom, 0 ≤ P ≤ 1, which measures a degree of polarization of the bonding molecular orbital (MO). They are compared with the MO predictions obtained from the same probability-division rule of the molecular bond-order measures from the MO theory. The atomic bond indices from the communication-theory approach are shown to agree semi-quantitatively with predictions from the MO theory.