Lanthanide salts solutions: representation of osmotic coefficients within the binding mean spherical approximation.
Osmotic coefficients of aqueous solutions of lanthanide salts are described using the binding mean spherical approximation (BIMSA) model based on the Wertheim formalism for association. The lanthanide(III) cation and the co-ion are allowed to form a 1-1 ion pair. Hydration is taken into account by introducing concentration-dependent cation size and solution permittivity. An expression for the osmotic coefficient, derived within the BIMSA, is used to fit data for a wide variety of lanthanide pure salt aqueous solutions at 25 degrees C. A total of 38 lanthanide salts have been treated, including perchlorates, nitrates, and chlorides. For most solutions, good fits could be obtained up to high ionic strengths. The relevance of the fitted parameters has been discussed, and a comparison with literature values has been made (especially the association constants) when available.
Ruas
Alexandre
A
CEA-Valrhô Marcoule, DEN/DRCP/SCPS/LCA, Bât 399, BP 17171, 30207 Bagnols-sur-Cèze Cedex, France.
Moisy
Philippe
P
Simonin
Jean-Pierre
JP
Bernard
Olivier
O
Dufrêche
Jean-François
JF
Turq
Pierre
P