{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,9,27]],"date-time":"2026-09-27T14:04:03Z","timestamp":1790517843715,"version":"4.1.0"},"reference-count":54,"publisher":"MDPI AG","issue":"24","license":[{"start":{"date-parts":[[2020,12,17]],"date-time":"2020-12-17T00:00:00Z","timestamp":1608163200000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100016394","name":"ANR","doi-asserted-by":"publisher","award":["ANR-16-CE07-0013-02"],"award-info":[{"award-number":["ANR-16-CE07-0013-02"]}],"id":[{"id":"10.13039\/501100016394","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Molecules"],"abstract":"<jats:p>The control of ligand-field splitting in iron (II) complexes is critical to slow down the metal-to-ligand charge transfer (MLCT)-excited states deactivation pathways. The gap between the metal-centered states is maximal when the coordination sphere of the complex approaches an ideal octahedral geometry. Two new iron(II) complexes (C1 and C2), prepared from pyridylNHC and pyridylquinoline type ligands, respectively, have a near-perfect octahedral coordination of the metal. The photophysics of the complexes have been further investigated by means of ultrafast spectroscopy and TD-DFT modeling. For C1, it is shown that\u2014despite the geometrical improvement\u2014the excited state deactivation is faster than for the parent pseudo-octahedral C0 complex. This unexpected result is due to the increased ligand flexibility in C1 that lowers the energetic barrier for the relaxation of 3MLCT into the 3MC state. For C2, the effect of the increased ligand field is not strong enough to close the prominent deactivation channel into the metal-centered quintet state, as for other Fe-polypyridine complexes.<\/jats:p>","DOI":"10.3390\/molecules25245991","type":"journal-article","created":{"date-parts":[[2020,12,17]],"date-time":"2020-12-17T21:21:49Z","timestamp":1608240109000},"page":"5991","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":39,"title":["Towards Iron(II) Complexes with Octahedral Geometry: Synthesis, Structure and Photophysical Properties"],"prefix":"10.3390","volume":"25","author":[{"given":"Mohamed","family":"Darari","sequence":"first","affiliation":[{"name":"Universit\u00e9 de Lorraine, CNRS, L2CM, F-54000 Nancy, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8232-4989","authenticated-orcid":false,"given":"Antonio","family":"Franc\u00e9s-Monerris","sequence":"additional","affiliation":[{"name":"Universit\u00e9 de Lorraine, CNRS, LPCT, F-54000 Nancy, France"},{"name":"Departament de Qu\u00edmica F\u00edsica, Universitat de Val\u00e8ncia, 46100 Burjassot, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-3142-8029","authenticated-orcid":false,"given":"Bogdan","family":"Marekha","sequence":"additional","affiliation":[{"name":"Max-Planck-Institute for Medical Research, 69120 Heidelberg, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Abdelatif","family":"Doudouh","sequence":"additional","affiliation":[{"name":"Universit\u00e9 de Lorraine, CNRS, CRM2, F-54000 Nancy, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Emmanuel","family":"Wenger","sequence":"additional","affiliation":[{"name":"Universit\u00e9 de Lorraine, CNRS, CRM2, F-54000 Nancy, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-9464-1463","authenticated-orcid":false,"given":"Antonio","family":"Monari","sequence":"additional","affiliation":[{"name":"Universit\u00e9 de Lorraine, CNRS, LPCT, F-54000 Nancy, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Stefan","family":"Haacke","sequence":"additional","affiliation":[{"name":"Universit\u00e9 de Strasbourg, CNRS, IPCMS, F-67034 Strasbourg, France"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4905-1581","authenticated-orcid":false,"given":"Philippe C.","family":"Gros","sequence":"additional","affiliation":[{"name":"Universit\u00e9 de Lorraine, CNRS, L2CM, F-54000 Nancy, France"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2020,12,17]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"6595","DOI":"10.1021\/cr900356p","article-title":"Dye-Sensitized Solar Cells","volume":"110","author":"Hagfeldt","year":"2010","journal-title":"Chem. 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