Electronegativities and isoelectronic energy and electronegativity differences for monatomic systems with nonintegral nuclear charges: local-spin-density-functional calculations

A relativistic self-consistent-field self-interaction-corrected local-spin-density functional, with electronic correlation included, has been used to compute the electronegativities of monatomic systems with nonintegral nuclear charges. We focused specifically upon quark atoms related to the halogens, having nuclear charges of Z±⅓. Two different methods for calculating electronegativities were found to give results in good agreement with each other and with an earlier empirical approach. It was also shown that accurate energy and electronegativity differences for the isoelectronic quark-atom pairs Z+⅓, Z−⅓ and Z+⅔, Z−⅔ can be determined using only the electrostatic potentials at the nuclei of the isoelectronic atoms and ions with integral nuclear charges