Visible and Infrared Spectroelectrochemistry of Cobalt Porphinones and Porphinediones

The visible and infrared spectroelectrochemistry of the redox chemistry of CoII–porphinone complexes were examined and compared with similar studies of the respective iron complexes. Cobalt(II) porphinone complexes undergo a one-electron reduction and two one-electron oxidations within the potential region that was studied in this work. The one electron spectroelectrochemical reduction of CoII(P) (P = octaethylporphyrin (OEP), octaethylporphinone (OEPone), and octaethylporphinedione (OEPdione)) were studied using visible spectroscopy, and their cobalt(I) complexes were characterized. The same reduction was examined by FTIR spectroscopy for P = OEPone and OEPdione. The infrared spectra showed downshifts of the νCO band that were consistent with a cobalt(I) complex and were similar to the iron(I) complex. The two one-electron oxidations of CoII(OEPone) and CoII(OEPdione) were also carried out using visible and infrared spectroelectrochemistry. The νCO band for cobalt was less sensitive to the metal oxidation state (III vs. II) than was observed in the iron complexes. Additional upshifts in the νCO band were observed for the π-cation radical. Isotopic 18O substitution on the carbonyl group of the H2OEPone was done in order to determine the degree of mixing up the porphinone modes with the carbonyl vibrations

Visible and Infrared Spectroelectrochemistry of Zinc and Manganese Porphinones: Metal vs. Porphyrin Reduction

The visible and infrared spectroelectrochemistry of zinc and manganese porphinones and porphinediones was carried out in THF solutions. The aim of this work was to use FTIR spectroelectrochemistry and DFT calculation to determine whether the reduction was centered predominantly on the metal or the macrocycle. For zinc(II), the first one-electron reduction must occur on the macrocyclic ring because the metal’s d-orbitals are filled (d10). The carbonyl bands on the macrocyclic ring were used to probe the electronic structure because they can be readily observed in the infrared spectra. The results of this study are complementary to previous spectroelectrochemical studies that have been reported for the iron and cobalt complexes of the same macrocycles. As expected for the formation of a π-radical anion species, significant downshifts in the carbonyl bands were observed. DFT calculations showed that the behavior of the porphinedione complexes were most sensitive to the electronic structure of the M(OEPdione)− species. If a MI species is formed, the two carbonyl groups will be downshifted by similar energies. For MII-radical anions, one carbonyl will be downshifted significantly, and the second one will be downshifted by a small amount. On the basis of this criterion, it was determined that cobalt(I) and iron(I) complexes were formed, while zinc and manganese formed π-radical anion species. The visible spectroelectrochemistry was also consistent with these electronic structures

Data governance support for business intelligence in higher education: a systematic literature review

Business Intelligence (BI) is important for achieving effective decision-making in higher education. This study, however, advocated the need to support BI with data governance in higher education. The systematic literature review was conducted using a qualitative approach. The study cover 2005– 2019. A total of 483 papers were retrieved and after exclusion and inclusion criteria, two hundred and three were removed due to lack of relevance. Some of the removed papers were those written in other languages other than the English language. Finally, one hundred and eighty were analyzed for this study. Some of those sources used for the study include Scopus, Springer, science direct, IEEE explore, Web of science. The results were arranged under word cloud, word frequency, Year-source by attribute, matrix coding by methodology, business intelligence, and its benefits, critical success factor, data governance, and its benefits, an overview of higher education and need to support business intelligence with data governance. The study provides information to higher education business intelligence experts on the need to support their BI with data governance