Electronegativity and the concept of charge capacity

Abstract

A general discussion of electronegativity and electronegativity equalization is presented as background for the concept of charge capacity; the latter is the ability of an atom to absorb or yield electronic charge. We have discussed charge capacity in relation to a variety of atomic and molecular properties, e.g. atomic polarizabilities and outer shell properties, electron affinities, dipole moments, electronic density distributions, dissociation energies, electrostatic potentials, spectroscopic measurements, acidities, etc. Significant increases in charge capacity and decreases in electronegativity in going from the first to subsequent rows of the periodic table are important in explaining (especially for columns IV–VII) the discontinuities in many physical and chemical properties that occur between these rows. It is demonstrated that both intrinsic electronegativities and charge capacities must be considered in order to understand the redistribution that occurs when atoms interact to form molecules. We discuss many seemingly anomalous observations of chemical behavior that are explained quite readily when both of these factors are taken into account.