PNNL

Abstract

A chemical bond is an interaction that should be detectable in the electron density distribution associated with a bonded pair of atoms. A common method for detecting the existence of a bond is to determine whether a bond path exists between the nuclei of the pair. However, especially for relatively weak secondary interactions, such as O-O bonded interaction, the existence of or non-existence of actual bond paths may be misleading. Other factors, external to the interactions between the atoms, may cause the appearance of a bogus bond path or may obliterate the existence of a bona fide path. For example, bond paths between O-O edge sharing equivalent and quasi-equivalent MOn coordinated polyhedra may well be artifacts due to the superposition of the electron density of nearby metal M atoms situated on opposite sides of the shared polyhedral edges. On the other hand, the bond path associated with a bona fide O-O bonded interaction may be disrupted by the electron density distribution of the nearby atoms. In fact, a disruption factor is defined that correctly separates the cases for which bond paths appear and for which they do not for a wide variety of O-O occurrences.