Details

Autor(en) / Beteiligte

• Sanchez, M.C
• Isolani, P.C
• Zukerman-Schpector, J
• Vicentini, G

Titel

Characterization and structure of hydrated scandium(III) picrate: complexes with sulfoxide ligands

Ist Teil von

• Journal of alloys and compounds, 2002-10, Vol.344 (1), p.298-303

Ort / Verlag

Lausanne: Elsevier B.V

Erscheinungsjahr

2002

Quelle

Alma/SFX Local Collection

Beschreibungen/Notizen

• Hydrated Sc(III) picrate was prepared and characterized by elemental analysis, Karl Fisher titration and its structure was determined by X-ray single crystal diffraction. The molecular formula determined was Sc(pic) 3·11.3H 2O (pic=picrate). The Sc(III) ion is heptacoordinated to six water molecules and one picrate anion, through its phenolic oxygen (monodentate). The coordination polyhedron is a monocapped trigonal prism, with one water oxygen in the cap position. The ligands tetramethylenesulfoxide (TMSO), dimethylsulfoxide (DMSO), 1,3-dithiane-1-oxide (DTSO), benzylphenylsulfoxide (BFSO) and diphenylsulfoxide (DFSO) form complexes with compositions: Sc(pic) 3·3TMSO; Sc(pic) 3·2.5DTSO·3H 2O; Sc(pic) 3·3DMSO·2H 2O; Sc(pic) 3·4BFSO and Sc(pic) 3·3DFSO·2H 2O. All complexes were characterized by elemental analysis, thermogravimetry and infrared spectroscopy. In all complexes νSO of the ligands appear at lower energies with relation to the free ligands, evidencing bonding through the sulfoxide oxygen. The ν sNO 2 and ν asNO 2 of the picrate anions evidence that in the complexes these anions are bidentate, coordinated through the phenolic and one o-nitrogroup oxygens. All complexes present luminescence with maxima between 518 and 520 nm. This was interpreted as phosphorescence of the picrate anion. Excitation spectra show absorption bands at 215 and 420 nm, also characteristic of picric acid and its salts.