Cobalt complexes with multi-dentate N-donor ligands: Redox, X-ray photoelectron spectroscopic and theoretical study
Five CoII complexes were prepared with different multi-dentate N-donor ligands (5-Nitro-1,10-phenanthroline, 1,10-phenanthroline, 2,2′:6′,2″-terpyridine, 2,2′-dipyridyl or 4,4′-dimethoxy-2,2′-bipyridine). Complexation was confirmed with the blue-shift of stretching frequency of the CN moiety of the...
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| Language: | English |
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Elsevier
2023-01-01
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| Series: | Results in Chemistry |
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| Online Access: | http://www.sciencedirect.com/science/article/pii/S2211715623000577 |
| _version_ | 1797799071214206976 |
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| author | Jeanet Conradie Elizabeth Erasmus |
| author_facet | Jeanet Conradie Elizabeth Erasmus |
| author_sort | Jeanet Conradie |
| collection | DOAJ |
| description | Five CoII complexes were prepared with different multi-dentate N-donor ligands (5-Nitro-1,10-phenanthroline, 1,10-phenanthroline, 2,2′:6′,2″-terpyridine, 2,2′-dipyridyl or 4,4′-dimethoxy-2,2′-bipyridine). Complexation was confirmed with the blue-shift of stretching frequency of the CN moiety of the ligands as measured by ATR FTIR and by XPS spectra. The average XPS binding energies (BE) of the main and satellite structures of Co 2p3/2 photoelectron lines for CoII were ca. 780.3 eV and 785.0 eV respectively. The diffusion controlled formal reduction potential E0′ of the CoII/III redox couple measured in aqueous medium ranged between 0.08 and 0.58 V versus NHE. Ihe CoII/I redox couple measured in DMF ranged between between −1.1 and −1.7 V vs HFc/HFc+. Directly proportional relationships were established between the E0′ of both the CoII/III and CoII/I redox couples and the BE of the main CoII 2p3/2 photoelectron lines and DFT calculated energies and charges. These relationships all illustrate the electronic influence of the different N-donor ligands on the effective charge of the central cobalt(II) ion the ligands are coordinated to, can be quantised by the different experimental redox and XPS BE values and DFT calculated electronic descriptors. |
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| format | Article |
| id | doaj.art-4788ee58bf6a441685e9ec0e8ae18d43 |
| institution | Directory Open Access Journal |
| issn | 2211-7156 |
| language | English |
| last_indexed | 2024-03-13T04:13:24Z |
| publishDate | 2023-01-01 |
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| spelling | doaj.art-4788ee58bf6a441685e9ec0e8ae18d432023-06-21T06:52:09ZengElsevierResults in Chemistry2211-71562023-01-015100818Cobalt complexes with multi-dentate N-donor ligands: Redox, X-ray photoelectron spectroscopic and theoretical studyJeanet Conradie0Elizabeth Erasmus1Corresponding authors.; Department of Chemistry, University of the Free State, PO Box 339, Bloemfontein 9300, South AfricaCorresponding authors.; Department of Chemistry, University of the Free State, PO Box 339, Bloemfontein 9300, South AfricaFive CoII complexes were prepared with different multi-dentate N-donor ligands (5-Nitro-1,10-phenanthroline, 1,10-phenanthroline, 2,2′:6′,2″-terpyridine, 2,2′-dipyridyl or 4,4′-dimethoxy-2,2′-bipyridine). Complexation was confirmed with the blue-shift of stretching frequency of the CN moiety of the ligands as measured by ATR FTIR and by XPS spectra. The average XPS binding energies (BE) of the main and satellite structures of Co 2p3/2 photoelectron lines for CoII were ca. 780.3 eV and 785.0 eV respectively. The diffusion controlled formal reduction potential E0′ of the CoII/III redox couple measured in aqueous medium ranged between 0.08 and 0.58 V versus NHE. Ihe CoII/I redox couple measured in DMF ranged between between −1.1 and −1.7 V vs HFc/HFc+. Directly proportional relationships were established between the E0′ of both the CoII/III and CoII/I redox couples and the BE of the main CoII 2p3/2 photoelectron lines and DFT calculated energies and charges. These relationships all illustrate the electronic influence of the different N-donor ligands on the effective charge of the central cobalt(II) ion the ligands are coordinated to, can be quantised by the different experimental redox and XPS BE values and DFT calculated electronic descriptors.http://www.sciencedirect.com/science/article/pii/S2211715623000577Multi-dentate N-donor ligandsCobaltCVDFTXPS |
| spellingShingle | Jeanet Conradie Elizabeth Erasmus Cobalt complexes with multi-dentate N-donor ligands: Redox, X-ray photoelectron spectroscopic and theoretical study Results in Chemistry Multi-dentate N-donor ligands Cobalt CV DFT XPS |
| title | Cobalt complexes with multi-dentate N-donor ligands: Redox, X-ray photoelectron spectroscopic and theoretical study |
| title_full | Cobalt complexes with multi-dentate N-donor ligands: Redox, X-ray photoelectron spectroscopic and theoretical study |
| title_fullStr | Cobalt complexes with multi-dentate N-donor ligands: Redox, X-ray photoelectron spectroscopic and theoretical study |
| title_full_unstemmed | Cobalt complexes with multi-dentate N-donor ligands: Redox, X-ray photoelectron spectroscopic and theoretical study |
| title_short | Cobalt complexes with multi-dentate N-donor ligands: Redox, X-ray photoelectron spectroscopic and theoretical study |
| title_sort | cobalt complexes with multi dentate n donor ligands redox x ray photoelectron spectroscopic and theoretical study |
| topic | Multi-dentate N-donor ligands Cobalt CV DFT XPS |
| url | http://www.sciencedirect.com/science/article/pii/S2211715623000577 |
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