The Madelung-Klechkowskii rule: origin, use as a teaching instrument and limitations

Abstract

It is carried out an initial historical analysis of the origin of the Madelung-Klechkowskii rule as well as of its rapid incorporation as a didactic instrument, which led to the proposal of numerous mnemonic rules to facilitate its learning. Subsequently, it is analysed the incorrect way with which this rule is usually mechanically applied, through a particular study of the electronic configurations of the elements of the first transition series. Finally, it is exemplified its limitations regarding the transition elements and their ions.