On the Misleading Interpretation of the Properties of the f‐Electron Elements

Abstract

SummaryThe aim of the paper is to elucidate the problem of the regular changes in the properties off-elements represented by the double-double effect. It is pointed out that because of the half-filled shell and double-double effects the f-element properties cannot be plotted as a linear function of the L-quantum number, as suggested bySinha reviews the various lanthanide properties and correlates them in terms of the 'inclined W' plots [ 11 [2]. This constitutes however a mislieading interpretation of the existing experimental data.Any consideration of the validity of the idea of 'inclined W' plots, should take into account (1) the half-filled shell effect [3], and (2) the double-double effect discovered in form of the 'regularities' in the separation factors or in stability constants [4]. The former effect, first demonstrated experimentally by Seaborg's group [5] using ion exchange chromatography, is based on the observation that the f6-and f7-electron elements are more similar to each other than those with the f'-and$-electron configurations.The main feature of the double-double effect is the analogy between the