Synthesis, characterization and thermal behavior of some addition compounds between rare earth picrates (pic) and 2,2′-dithiobis(pyridine-N-oxide)

• Published in: Thermochimica acta Vol. 344; no. 1; pp. 67 - 72
• Main Authors: Marinho, E.P, de Sousa, W.S.C, Melo, D.M.A, Zinner, L.B, Zinner, K, Mercuri, L.P, Vicentini, G
• Format: Journal Article Conference Proceeding
• Language: English
• Published: Amsterdam Elsevier B.V 28.01.2000; Elsevier Science
• Subjects: 2,2′-Dithiobis(pyridine-N-oxide); Chemistry; Coordination compounds; Exact sciences and technology; Inorganic chemistry and origins of life; Picrates; Preparations and properties; Rare earth; Synthesis and characterization; Thermogravimetry; Picrates; Rare earth; Synthesis and characterization; Thermogravimetry; 2,2′-Dithiobis(pyridine-N-oxide); Pyrolysis; Thermal decomposition; Rare earth metal complex; Nitrone; Preparation; Organic ligand; Picric acid; Experimental study; Degradation product; Adduct
• ISSN: 0040-6031; 1872-762X
• DOI: 10.1016/S0040-6031(99)00328-7

Rare earth picrates addition compounds with 2,2′-dithiobis(pyridine-N-oxide) (dithio) were synthesized and characterized. CHN analysis suggest a general formula Ln(pic) 3·1.5dithio·4H 2O (Ln = La, Nd, Eu, Dy, Ho). IR spectra indicate: (a) the presence of water molecules; (b) the presence of picrate in bidentade form; and (c) a bond of dithio to the RE through NO groups. Parameters, calculated from Nd absorption spectra at room temperature are in agreement with a small covalent character of the Ln:L interaction. Thermogravimetric data under N 2 and air atmospheres, show that: (a) the water molecules loss is the first decomposition step (up to 453 K); (b) the residue, at ca. 1173 K, is essentially Ln 2O 3.