Characteristic features of the electrostatic potentials of singly negative monoatomic ions

Abstract

We show that a monoatomic negative ion has a minimum in its electrostatic potential V(r) occurring at the radial distance r_m that encompasses a quantity of electronic charge exactly equal to the nuclear charge. Thus, V(r_m) is due entirely to the excess electronic charge on the ion. We suggest that r_m can be identified with the radius of the ion, while V(r_m) indicates the strength of its interactions with positive ions.