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Lanthanide nitrate complexes with 1,3-dithiane-1-oxide (DTSO)

2002; Elsevier BV; Volume: 344; Issue: 1-2 Linguagem: Inglês

10.1016/s0925-8388(02)00316-x

1873-4669

Paulo B. Miranda, Claide P. Moraes, Maria P. Araújo, J. R. Matos, P.C. Isolani, G. Vicentini, L.B. Zinner,

Crystal structures of chemical compounds

Lanthanide nitrate complexes with 1,3-dithiane-1-oxide (DTSO) were synthesized by reaction of the hydrated lanthanide nitrates with DTSO in triethyl-ortho-formate. Complexometric analyses with EDTA and CHN microanalytical procedures are indicative of a general formula Ln(NO3)3·3DTSO, where Ln=Nd–Lu and Y. IR absorption spectra were interpreted in terms of DTSO and nitrate anion coordination through the oxygen atoms. Conductance measurements in acetonitrile solutions showed that the complexes behave as non-electrolytes. The parameters obtained from the absorption spectrum of the Nd(III) compound indicated weakly covalent metal–ligand bonds. The 5D0→7FJ (J=1,2,3) transitions for the emission spectrum of the Eu(III) compound were interpreted in terms of a C3v symmetry. X-ray powder patterns showed only one isomorphous series. Thermogravimetry results (under air, 50 ml min−1 and 10 °C min−1 heating rate) showed that one DTSO molecule and the nitrate ions are liberated at ca. 300 °C and the other ligands are decomposed in three events until 900 °C leaving lanthanide oxysulfates as residues.