66745-65-1Relevant academic research and scientific papers
Cyclic voltammetric wave symmetry and peak current calculations as confirmation of the reversible, sequential transfer of two electrons at very similar potentials in bis(1,3,5-triketonato)dicopper(II) complexes and their diamine Schiff bases. Comparison between mono- and binuclear complexes and a study of the effect of Na+ and Li+ on the electron-transfer process
Lintvedt,Ranger,Schoenfelner
, p. 688 - 695 (2008/10/08)
The cyclic voltammetry of a series of related mono- and binuclear Cu(II) complexes of 1,3,5-triketonates and their diamine Schiff-base derivatives has been investigated in a scan range of greater than 103 V/s in both the presence and absence of simple cations such as Na+ and Li+. In all cases the mononuclear complexes exhibit irreversible electron transfer while the binuclear complexes in both the presence and absence of simple cations exhibit reversible electron transfer over a wide scan rate range. In the absence of Na+ or Li+ there is one CV wave in the 0- to -1.7-V region for each of the binuclear complexes, which occurs between about -0.8 and -1.1 V vs. SSCE. On the basis of wave symmetry and peak current calculations, this wave is attributed to a reversible, one-electron transfer. Addition of an excess of Na+ or Li+ results in a +300-mV shift of the wave, a large increase in the peak currents, a decrease in ΔEp, and a decrease in Epc - Epc/2. Peak current calculations together with ΔEp and Epc - Epc/3 values confirm that the electron-transfer process is the reversible, sequential transfer of two electrons at very nearly the same potentials. The single wave in the 0- to -1.7-V region occurs from about -0.4 to -0.8 V vs. SSCE, depending upon the ligand. In each case the shapes of the CV waves for the simple binuclear triketonates and the diamine Schiff-base derivatives are virtually the same under identical experimental conditions. The only significant difference between the CV properties of the two classes is that the Schiff-base complexes have reduction potentials about 150 mV more negative than the parent triketonate complex.
