Solvent Phase Optimizations Improve Correlations with Experimental Stability Constants for Aqueous Lanthanide Complexes

Stability constants provide insight into ion complexation in water. While computational studies have been shown to model the energy of successfully using a thermodynamic cycle approach, it does not extend calculating stability for 1:1 lanthanide ligand complexes solution. Using B3LYP and 6-31+G* Pople basis with small core effective potential (ECP) on lanthanum ion, solvent based full solute electron density (SMD) solvation we computed compared previously published ligands: acetate, acetohydroximate, acetylacetonate, methanoate, tropolonate, hydroxide, catecholate, malonate, oxalate, phthalate, sulfate. The best R2 values can only be determined by separating mono divalent ions achieve an value 0.86 0.74 ions, respectively. We show that optimizing lanthanide-ligand structures implicit solvent, improved correlation between experimental 0.89 combined ions.