{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,4,25]],"date-time":"2026-04-25T01:52:12Z","timestamp":1777081932923,"version":"3.51.4"},"reference-count":40,"publisher":"Frontiers Media SA","license":[{"start":{"date-parts":[[2023,11,15]],"date-time":"2023-11-15T00:00:00Z","timestamp":1700006400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":["frontiersin.org"],"crossmark-restriction":true},"short-container-title":["Front. Chem."],"abstract":"<jats:p>Reaction of nickel and zinc triflates with the tridentate leucoverdazyl 1-isopropyl-3,5-di (2\u2032-pyridyl)-6-oxo-2H-tetrazine (dipyvdH) and triethylamine resulted in the neutral coordination compounds M(dipyvd)<jats:sub>2<\/jats:sub> (M = Ni,Zn). In acetonitrile, both compounds undergo two one electron oxidation processes, Zn (dipyvd)<jats:sub>2<\/jats:sub>\u00a0at \u22120.28\u00a0V and \u22120.12\u00a0V and Ni(dipyvd)<jats:sub>2<\/jats:sub>\u00a0at \u22120.32\u00a0V and \u22120.15\u00a0V vs ferrocene\/ferricenium. Oxidations are ligand based resulting in an intermediate mixed valence species and a cationic bis(verdazyl) compound respectively. Oxidation of the ligand changes a localized, antiaromatic, non-planar 8\u03c0 electron anion to a planar, delocalized 7\u03c0 electron radical. The change in ligand structure results in an increase in the octahedral ligand field splitting from 10,500\u00a0cm<jats:sup>\u20131<\/jats:sup> to \u223c13,000\u00a0cm<jats:sup>\u20131<\/jats:sup>, suggesting an increase in the pi acceptor character of the ligand. In the mixed valence species, spectroscopic data suggests minimal interaction between ligands mediated by the metal center; i.e., these are class I-II systems in the Robin-Day classification.<\/jats:p>","DOI":"10.3389\/fchem.2023.1295289","type":"journal-article","created":{"date-parts":[[2023,11,15]],"date-time":"2023-11-15T09:20:18Z","timestamp":1700040018000},"update-policy":"https:\/\/doi.org\/10.3389\/crossmark-policy","source":"Crossref","is-referenced-by-count":6,"title":["Metal-ligand interactions in a redox active ligand system. Electrochemistry and spectroscopy of [M(dipyvd)2]n+ (M=Zn, Ni, n=0, 1, 2)"],"prefix":"10.3389","volume":"11","author":[{"given":"Connor","family":"Fleming","sequence":"first","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"Son","family":"Vu","sequence":"additional","affiliation":[],"role":[{"role":"author","vocabulary":"crossref"}]},{"given":"David J. 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