Dependence of the stability of lanthanide β-dicarbonyl complexes on the metal—ligand bond energy

Mishchenko, AM
Trunova, EK
Dopov. Nac. akad. nauk Ukr. 2019, 4:74-80
Section: Chemistry
Language: Russian

The formation constants of the lanthanide complexes with acetylacetone, methyl, and ethyl acetoacetate are determined by pH-potentiometric titration in a water-ethanol solution. Their stability is shown to correlate with the energy of the metal–ligand ionic bond calculated using the semiempirical Sparkle/PM7 method. Higher values of the overall formation constants of the lanthanide complexes with β-ketoesters are caused by the strengthening of the metal–ligand electrostatic interaction due to an increase of the negative charge on the ligand carbonyl oxygen atoms.

Keywords: formation constants, ionic bonding, lanthanide complexes, semiempirical calculations, β-dicarbonyl ligands

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