On the Modeling of the S-Shaped Thermodynamic and Transport Behavior against the Atomic Number Z of Some Trivalent f-Element Ions in Aqueous Solutions at 298 K and Prediction for Completion of the Periodic Table of Chemical Elements

Abstract

Ionic self-diffusion coefficients D of some trivalent lanthanide and actinide ions have been determined by the open-end capillary method (O.E.C.M.) in supporting lanthanide electrolyte 1 : 3 aqueous solutions at 25°C and optimal pH 2.50 in order to avoid hydrolysis, ion pairing and complexing of trivalent 4f ions. This study contributes to demonstrate similarities in transport and structure properties between 4f and 5f trivalent ions explained by a similar electronic configuration, ionic radius and same hydration number. These similarities are manifested in a strong causal correlation between certain properties by linear or S-shaped behaviors. In this context, we have suggested some expressions relating these properties and interesting to estimate or predict, by interpolation or extrapolation methods, some eventually not available experimental values, especially for the actinides for which the half-life is very short or the experimental conditions are very special and expensive. For this issue, we can contribute to the complement of periodic table of elements by some physicochemical properties, especially for the 5f-series, when we have some available data on the 4f‑series as well as the mathematical function of the causal correlation between these two nf-series.