By studying the relation between the absolute hardness h and nl in different cases, and by using the relation of Z'/nl to the Mulliken electronegativity, electron affinities (A) are correlated simultaneously with Z'/nl and nl, thereby giving rise to the following equation A = aZ'/nl + bnl + c where a, b and c are constants The authors have done so for each column and transition series in the Periodic Table. Almost all the calculated results are in a good agreement with the existing experimental values, and the correlation coefficients are high. The method provides an easy and feasible way for studying systematic trends of electron affinities. The phys. essence of this correlation is elucidated, and the results are discussed.

Key words: QUANTUM CHEMISTRY, RULES, MOLECULAR ORBITAL THEORY, ELECTRONEGATIVITY, ELECTRON AFFINITY, QUANTUM NUMBERS, PERIODIC TABLE OF THE ELEMENTS