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Eclética Química

Print version ISSN 0100-4670

Abstract

FERENC, W.; BERNAT, M.; SARZYńSKI, J.  and  GłUCHOWSKA, H.. Complexes of 4-chlorophenoxyacetates of Nd(III), Gd(III) and Ho(III). Eclet. Quím. [online]. 2010, vol.35, n.1, pp. 67-75. ISSN 0100-4670.  http://dx.doi.org/10.1590/S0100-46702010000100008.

The complexes of 4-chlorophenoxyacetates of Nd(III), Gd(III) and Ho(III) have been synthesized as polycrystalline hydrated solids, and characterized by elemental analysis, spectroscopy, magnetic studies and also by X-ray diffraction and thermogravimetric measurements. The analysed complexes have the following colours: violet for Nd(III), white for Gd(III) and cream for Ho(III) compounds. The carboxylate groups bind as bidentate chelating (Ho) or bridging ligands (Nd, Gd). On heating to 1173K in air the complexes decompose in several steps. At first, they dehydrate in one step to form anhydrous salts, that next decompose to the oxides of respective metals. The gaseous products of their thermal decomposition in nitrogen were also determined and the magnetic susceptibilites were measured over the temperature range of 76-303K and the magnetic moments were calculated. The results show that 4-chlorophenoxyacetates of Nd(III), Gd(III) and Ho(III) are high-spin complexes with weak ligand fields. The solubility value in water at 293K for analysed 4-chlorophenoxyacetates is in the order of 10-4mol/dm3.

Keywords : 4-chlorophenoxyacetates; thermal stability; magnetic properties of Nd(III); Ho(III); Gd(III).

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