Magnetic, thermal and spectroscopic properties of lanthanide(III) 2-(4-chlorophenoxy)acetates, Ln(C8H6ClO3)3 ⋅ nH2O.

2-(4-Chlorophenoxy)acetates of lanthanides(III) were synthesized as polycrystalline hydrated solids with the general formulae: Ln(C8H6ClO3)3⋅2H2O (Ln = La(III), Pr(III), Sm(III), Eu(III) or Tb(III)); Ln(C8H6ClO3)3⋅H2O (Ln = = Dy(III)) and Ln(C8H6ClO3)3⋅3H2O (Ln = Er(III), Tm(III), Yb(III) and Lu(III). The complexes were characterized by elemental analysis, FTIR spectroscopy, magnetic and thermogravimetric studies and X-ray diffraction (XRD) analysis. The complexes have colours typical for the lanthanide(III) ions. The carboxylate groups bind as bidentate chelating agents. On heating to 1273 K in air, the complexes decompose in three steps. First they dehydrate in one stage to form anhydrous salts that then decompose to the oxides of the respective metals with the intermediate formation of their oxychlorides. The gaseous products of the thermal decomposition of the compounds under nitrogen were also determined. The magnetic susceptibilities of the complexes were measured over the ranges 76-303 K and 1.8-303 K, and their magnetic moments were calculated. The results showed that the 2-(4-chlorophenoxy)acetates of lanthanides(III) are high-spin complexes with weak ligand fields. [ABSTRACT FROM AUTHOR]