2-Mercaptobenzoxazole pentacyanoferrate(II/III) complexes: UV-Visible, Mössbauer, electron paramagnetic resonance, electrochemistry and molecular modeling

• Autor(a) principal: Luiz,Juciane B
• Data de Publicação: 2004
• Outros Autores: Andrade,Fabiano M. de, Sá,Eduardo L. de, Friedermann,Geraldo R, Mangrich,Antonio S, Barclay,J. Elaine, Evans,David J, Hasegawa,Tai, Nunes,Fábio S
• Tipo de documento: Artigo
• Idioma: eng
• Título da fonte: Journal of the Brazilian Chemical Society (Online)
• Texto Completo: http://old.scielo.br/scielo.php?script=sci_arttext&pid=S0103-50532004000100003
• topic: 2-mercaptobenzoxazole; pentacyanoferrate; spectroscopy; crystal field parameters; ab initio calculations; electrochemistry

2-Mercaptobenzoxazole pentacyanoferrate(II/III) complexes, [FeII/III(CN)5(bzoxs)]3-/2- , were prepared in MeOH/H2O 75:25% solutions and characterized by spectroscopic UV-Vis, Mössbauer, electron paramagnetic resonance (epr) and electrochemical-cyclic voltammetry- techniques. UV-Vis and epr spectra along with the electrochemical behavior suggested the coordination of the multi-functional N,S,O- donor ligand, bzoxs, to iron(III) through the sulfur atom. The crystal field parameters, DqL and Dt, calculated for the iron(II) complex, in addition to the reversible redox process FeIII-bzoxs + e- -> FeII-bzoxs also pointed to coordination via the sulfur atom. The results were compared with the chemical properties of pentacyanoferrate complexes containing other monodentate N-, S- and O-donor ligands. Ab initio calculations revealed the composition of the frontier orbitals of bzoxs and are in agreement with the mode of coordination proposed from the experimental data.