dc.contributor.author | Cao, Rui | |
dc.contributor.author | Thomas, Kolle E. | |
dc.contributor.author | Ghosh, Abhik | |
dc.contributor.author | Sarangi, Ritimukta | |
dc.date.accessioned | 2021-02-05T13:21:24Z | |
dc.date.available | 2021-02-05T13:21:24Z | |
dc.date.issued | 2020-05-29 | |
dc.description.abstract | A combination of Cr K-edge XAS and DFT calculations have been performed on archetypal chromium porphyrinoid complexes Cr<sup>IV</sup>[TMP]O (<b>2</b>) and Cr<sup>V</sup>[TPC]O (<b>3</b>), and the results have been compared to the reference compound Cr<sup>III</sup>[TPP]Cl (<b>1</b>), where TPP<sup>2−</sup>, TMP<sup>2−</sup>, and TPC<sup>3−</sup> are the anions of <i>meso</i>-tetraphenylporphyrin, <i>meso</i>-tetramesitylporphyrin, and <i>meso</i>-triphenylcorrole, respectively. The intensity-weighted average energy position in <b>1</b> (5990.9 eV), <b>2</b> (5992.0 eV) and <b>3</b> (5992.6 eV) are consistent with increasing the metal oxidation state along the series. EXAFS and theoretical analysis of <b>2</b> and <b>3</b> reveal that the Cr–O bond is longer and weaker in <b>3</b> relative to <b>2</b>, despite the structural similarity and increase in oxidation state in <b>3</b>. This is also reflected in a comparison of the Cr K-pre-edge transitions. The roughly twenty-fold increase in intensity in the two oxo complexes is unsurprising and well-precedented for other first-row transition metals. However, although <b>3</b> had greater overall intensity, the intensity of transitions along the Cr–O bond is greater. EXAFS, DFT and TDDFT analyses show that the more contracted N<sub>4</sub> core of the corrole results in a greater out-of-plane displacement of the Cr in <b>3</b> relative to <b>2</b>, which in turn accentuates the lower local symmetry of the Cr in <b>3</b> relative to <b>2</b>. This difference helps us to appreciate the TDDFT result that whereas two 1s→ 3d<sub>z2</sub> transitions make up the majority of the intensity in the pre-edge of <b>2</b>, the pre-edge of <b>3</b> also includes fairly intense transitions to molecular orbitals with 3d<sub>xz</sub>, 3d<sub>yz</sub> and 3d<sub>z2</sub> character, thus accounting for the somewhat higher overall intensity for <b>3</b>. | en_US |
dc.identifier.citation | Cao, R., Thomas, K.E., Ghosh, A. & Sarangi, R. (2020). X-ray absorption spectroscopy of archetypal chromium porphyrin and corrole derivatives. <i>RSC Advances, 10</i>, 20572-20578. | en_US |
dc.identifier.cristinID | FRIDAID 1849648 | |
dc.identifier.doi | https://doi.org/10.1039/D0RA02335C | |
dc.identifier.issn | 2046-2069 | |
dc.identifier.uri | https://hdl.handle.net/10037/20524 | |
dc.language.iso | eng | en_US |
dc.publisher | Royal Society of Chemistry | en_US |
dc.relation.journal | RSC Advances | |
dc.relation.projectID | info:eu-repo/grantAgreement/RCN/NANO2021/262229/Norway/Metallocorroles for photodynamic therapy and bioimaging// | en_US |
dc.rights.accessRights | openAccess | en_US |
dc.rights.holder | Copyright 2020 The Author(s) | en_US |
dc.subject | VDP::Mathematics and natural science: 400::Chemistry: 440 | en_US |
dc.subject | VDP::Matematikk og Naturvitenskap: 400::Kjemi: 440 | en_US |
dc.title | X-ray absorption spectroscopy of archetypal chromium porphyrin and corrole derivatives | en_US |
dc.type.version | publishedVersion | en_US |
dc.type | Journal article | en_US |
dc.type | Tidsskriftartikkel | en_US |
dc.type | Peer reviewed | en_US |