Spectroelectrochemical study of the copper(II) transfer assisted by 6,7-dimethyl-2,3-di(2-pyridyl)quinoxaline at the water vertical bar 1,2-dichloroethane interface

• Tipo: Artigo em Revista Científica Internacional
• Data: 1998

Autores

Tomaszewski, L (Autor) Outra; Ding, ZF (Autor) Outra; Fermin, DJ (Autor) Outra; Cacote, HM (Autor) Outra; Pereira, CM (Autor) FCUP; Silva, F (Autor) FCUP; Girault, HH (Autor) Outra

Revista

A Revista está pendente de validação pelos Serviços Administrativos.

Título: JOURNAL OF ELECTROANALYTICAL CHEMISTRY

Vol. 453

Páginas: 171-177

ISSN: 0022-0728

Indexação

ISI Web of Knowledge - 30 Citações

Scopus - 32 Citações

Classificação Científica

FOS: Ciências exactas e naturais > Química

Outras Informações

ID Authenticus: P-001-7A0

DOI: 10.1016/s0022-0728(98)00183-1

Abstract (EN): The assisted transfer of Cu(II) by interfacial complexation with 6,7-dimethyl-2,3-di(2-pyridyl)quinoxaline (DMDPQ) is studied at the polarised water\1,2-dichloroethane junction. Thermodynamic and kinetic aspects were addressed by cyclic voltammetry and in situ spectrophotometric measurements. The dependence of the half wave transfer potential on the ligand concentration suggests that the equilibrium is effectively displaced towards a 1:3 (metal:ligand) stoichiometry, with an association constant of log beta(3)degrees = 26.0. Visible spectra recorded by reflection from the aqueous phase showed the presence of two absorption bands at 400 and 500 nm associated with the Cu(II) complex. Chronoabsorptometric studies in the presence of a ligand excess suggest that the assisted transfer kinetics are effectively controlled by the diffusion of the metal ion to the interface.

Idioma: Inglês

Tipo (Avaliação Docente): Científica

Nº de páginas: 7