Related Experiment Video
Updated: Jan 1, 2026

Tuning Oxide Properties by Oxygen Vacancy Control During Growth and Annealing
Published on: June 9, 2023
Stabilization of the Oxidation State +IV in Siloxide-Supported Terbium Compounds
Aurélien R Willauer1, Chad T Palumbo1, Rosario Scopelliti1
1Institut des Sciences et Ingénierie Chimiques, Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015, Lausanne, Switzerland.
Abstract:
The synthesis of lanthanides other than cerium in the oxidation state +IV has remained a desirable but unmet target until recently, when two examples of TbIV with saturated coordination spheres were isolated. Here we report the third example of an isolated molecular complex of terbium(IV), where the supporting siloxide ligands do not saturate the coordination sphere. The fully characterized six-coordinate complex [TbIV (OSiPh3 )4 (MeCN)2 ], 2-TbPh , shows high stability and the labile MeCN ligands can be replaced by phosphinoxide ligands. Computational studies suggest that the stability is due to a strong π(O-Tb) interaction which is stronger than in the previously reported TbIV complexes. Cyclic-voltammetry experiments demonstrate that non-binding counterions contribute to the stability of TbIV in solution by destabilizing the +III oxidation state, while alkali ions promote TbIV /TbIII electron transfer.
Related Concept Videos
Properties of Transition Metals
Oxidation of Alkenes: Syn Dihydroxylation with Osmium Tetraoxide
Hydroboration-Oxidation of Alkenes
Redox Titration: Other Oxidizing and Reducing Agents
Complexation Equilibria: Factors Influencing Stability of Complexes
Radical Substitution: Hydrogenolysis of Alkyl Halides with Tributyltin Hydride
The bonds formed in this reaction are stronger than the bonds broken, making it energetically favorable. The reaction follows a radical chain mechanism similar to radical halogenation reactions,...

