1. The chemical consequences of the gradual decrease of the ionic radius along the Ln-series
- Author
-
Kristina Djanashvili, J. A. Peters, Carlos F. G. C. Geraldes, and Carlos Platas-Iglesias
- Subjects
Lanthanide ,Lanthanide contraction ,Steric effects ,Aqueous solution ,Ionic radius ,010405 organic chemistry ,Chemistry ,Solution structures ,010402 general chemistry ,01 natural sciences ,NMR ,0104 chemical sciences ,Ion ,Inorganic Chemistry ,Chemical physics ,Materials Chemistry ,Computational methods ,Atomic number ,Physical and Theoretical Chemistry ,Valence electron ,X-ray crystallography - Abstract
[Abstract] In the periodical system, the lanthanides (the 15 elements in the periodic table between barium and hafnium) are unique in the sense that their trivalent cations have their valence electrons hidden behind the 5s and 5p electrons. They show a gradual decrease in ionic radius with increasing atomic number (also known as the lanthanide contraction). The resulting steric effects determine to a large extent the geometries of complexes of these ions. Here, we discuss these effects, particularly upon the properties of the complexes in aqueous solution, for selected families of Ln3+-complexes of oxycarboxylate and aminocarboxylate ligands. The physical properties of the cations are very different, which is very useful for the elucidation of the configuration, conformation and the dynamics of the complexes by X-ray techniques, NMR spectroscopy, and optical techniques. Often the structural analysis is assisted by computational methods.
- Published
- 2019