title: Complexation of 5-fluorosalicylic acid with copper(II): a pH-potentiometric, UV-vis spectroscopic, and electron spin resonance study by the two-dimensional simulation of spectra.
abstract: The copper(II)-5-fluorosalicylic acid system was investigated in water and 50 v/v% water-methanol mixture by pH potentiometry combined with UV-vis spectrophotometry, and by the two-dimensional ESR simulation method, respectively. The data revealed that the stable paramagnetic mono- and bis(salicylato) copper(II) complexes [CuLH(-1)] and [CuL2H(-2)](2-) are formed, and at low excess of ligand, the ESR-silent mixed hydroxo complex [Cu2L2H(-3)](-) is also a major species. By the two-dimensional ESR simulation method, the species [CuL]+ in the acidic region, and the minor dimer [Cu2L2H(-2)] were also identified, and the cis and trans isomers of [CuL2H(-2)](2-) were characterized. In frozen solutions, the ESR analysis revealed a slight rhombic distortion of coordination polyhedra for the latter three species.
authors.affiliation: Department of Physical Chemistry, University of Szeged, P.O. Box 105, H-6701 Szeged, Hungary. szabot@chem.u-szeged.hu
authors.forename: Terézia
authors.initials: T
authors.lastname: Szabó-Plánka
authors.forename: Béla
authors.initials: B
authors.lastname: Gyurcsik
authors.forename: Nóra Veronika
authors.initials: NV
authors.lastname: Nagy
authors.forename: Antal
authors.initials: A
authors.lastname: Rockenbauer
authors.forename: Rastislav
authors.initials: R
authors.lastname: Sípos
authors.forename: Jozef
authors.initials: J
authors.lastname: Sima
authors.forename: Milan
authors.initials: M
authors.lastname: Melník
mesh_terms: D016880:Anisotropy; D002413:Cations, Divalent / Q000737:chemistry; D003198:Computer Simulation; D003300:Copper / Q000737:chemistry*; D004578:Electron Spin Resonance Spectroscopy; D006863:Hydrogen-Ion Concentration; D011199:Potentiometry; D012459:Salicylates / Q000737:chemistry*; D013056:Spectrophotometry, Ultraviolet
chemical_list: D002413:Cations, Divalent; D012459:Salicylates; C075234:5-fluorosalicylic acid; D003300:Copper