It is noteworthy that cobalt's coordination geometry can vary, exhibiting octahedral and tetrahedral forms, depending on the ligand and oxidation state. While cobalt (II) forms octahedral complexes with Versatic 10, it exhibits a preference for tetrahedral coordination with Cyanex 272 and its mixtures . This flexibility in coordination number is further demonstrated in the formation of mixed-valence cobalt complexes, where cobalt (III) adopts octahedral coordination while cobalt (II) maintains tetrahedral geometry .