Theoretical Studies on Lanthanide Cation Extraction by Picolinamides: Ligand-Cation Interactions and Interfacial Behavior

• Published in: Solvent extraction and ion exchange Vol. 21; no. 2; pp. 199 - 220
• Main Authors: Baaden, M., Berny, F., Madic, C., Schurhammer, R., Wipff, G.
• Format: Journal Article
• Language: English
• Published: Taylor & Francis Group 05-01-2003; Taylor & Francis
• Subjects: Cation extraction; Chelating ligands; Chemical Sciences; Interface; Modeling; or physical chemistry; Picolinamide; Theoretical and; Cation extraction; Picolinamide; Modeling; Interface; Chelating ligands
• ISSN: 0736-6299; 1532-2262
• DOI: 10.1081/SEI-120018946

We report theoretical investigations on the complexation and liquid-liquid extraction of trivalent lanthanide cations by picolinamide ligands L. The relative contributions of pyridine vs. amide moieties of L and the effect of alkyl substituents are investigated in the gas phase by quantum mechanical calculations. The uncomplexed ligands L with different lipophilic substituents and Eu(NO
3
)
3
L
3
complexes are simulated at a water-"oil" interface, where "oil" is modeled by chloroform. The simulations point to the importance of interfacial phenomena in the liquid-liquid extraction of cations by picolinamide ligands and the difference between pyridine vs. amide substituted ligands.