[en] Published in summary form only

[en] This chapter deals with the preparation of lanthanide complexes. It emphasizes the necessity of selecting a suitable starting material for each synthesis specially if the latter is carried out in anhydrous media. A few preparation techniques have been selected for each class of ligands. These techniques should allow the synthesis of a range of new lanthanide complexes. (author). 107 refs

[en] The absorption spectra corresponding to 4f electron transitions of the neodymium complex with xylenol orange and cetylpyridinium chloride in the presence of Triton X-100 are reported. The absorption by neo-dymium is increased by factor 666, compared with that of its chloride. Fourth-derivative spectra are used to increase the sensitivity and to eliminate interferences from other rare elements. Beer's law is obeyed for 1.4-7.2 μg Nd in 25 ml of solution. Relative standard deviation is 0.8% for 5.0 μg/25 ml (n=7). Detection limits are 5.0 ng ml^-1 for Nd alone and 11.0 ng ml^-1 in the presence of 45 ng of lanthanum. Satisfactory results were obtained for the determination of neodymium in rare earth mixtures. (author). 11 refs.; 4 figs

[en] Short communication. 3 refs

[en] Some urazole lanthanide complexes of Ln₂ (urazole)₃ composition were prepared (Ln=Pr, Nd and Ho) and characterized by their physical and chemical properties, analytical procedure and infrared spectroscopy; On the basis of spectral data it may be suggested that the coordination of tripositive lanthanide ions to the organic ligand occurs through the carbonyl group oxygen. IR data analysis indicates, as well, that one of the three urazole N-H groups suffers deprotonation. The structure of the complexes seems to be polymeric, however X-ray cristal diffraction is imperative for a conclusive determination. (author)

[en] The complexes of some rare earths [Ce(III), Pr(III), Nd(III), Sm(III), Tb(III), Dy(III) and Ho(III)] with 5-chloropyridine-2,3-diol (CPD) were studied potentiometrically in 50% dioxane-water at a ionic strength of 0.1 M (NaClO₄) at 35+-0.1⁰C. The proton-ligand stability constant of CPD and the stability constants of its complexes with the metals have been determined using the Calvin-Bjerrum technique as modified by Irving and Rossotti. The order of the stability constants is found to be Ce < Pr < Nd < Sm < Tb < Dy < Ho. (Author)

[en] The macrocyclic compounds 1,4,7,14,23-pentaoxa[7,2] orthocyclo[2] (2-6)pyridinophan; (DBP18C6) and 1,4,7,14,17,20-hexaoxa[7,7] orthocyclophan; (DB1SC6), used as ligands in the complexes with Eu(ClO₄)₃ and Tb(ClO)₄₃, were examined. A series of absorption spectra of Eu(III) - DBP18C6 and Tb(III) - DBP18C6 complexes was obtained by spectrophotometric titration with the lanthanide ions as a tritrant and using CH₃CN and CH₃OH as solvent at different volume ratios. The analysis of absorption spectra has shown a different influence of the mixed solvent on absorbance of the complexes investigated. An analogous investigation carried out with DBP18C6 similar to DBP18C6 has led to the conclusion that the presence of the pyridine ring in DBP18C6 influence the effect observed. (author). 9 refs, 3 refs, 1 tab

[en] Published in summary form only

[en] The chelation behaviour of complexes of La(3), Pr(3), Nd(3), Sm(3), Y(3), Tb(3), Dy(3), Ho(3) with ω-benzoyl-2-hydroxy-4-methoxy-3-methyl-acetophenone has been studied potentiometrically in 75% (v/v) aqueous alcohol medium at various ionic strengths. The method of Bjerrum and Calvin, as modified by Irving and Rossotti, has been used to find values of n-bar and pL. The stability constants and the values of S_min have been calculated. The order of stability constants was found to be: La < Pr < Nd < Sm < Y < Tb < Dy < Ho. (Author)

[en] Published in summary form only