Electron Delocalization Caused in 3d Complexes by Azide and Chloride Ligands Checked by Positronium Spin-Exchange Reactions

Abstract

The rate constants k _CR of orthointo para-positronium conversion reactions promoted by 3d complexes are linearly correlated with the electron delocalization of unpaired metal electrons caused by ligands, as measured by the ratio β between the interelectronic repulsion parameters in complexes and in the free gaseous ions (1 > β ≥ 0). The β values may be evaluated by means of the following empirical equation: β = 1 t _M h _L, where t _M and h _L are characteristic constants of 3d ions and ligands, respectively. By measuring k _CR and applying the correlations mentioned above, h _L constants may be derived providing that t _M is known. The method was used to measure the h _L value of N⁻ ₃, not yet known, and to check that of Cl⁻ ligand.