Pandey, PragatiWang, XiaoyuGupta, HimanshuSmith, Patrick W.Lapsheva, EkaterinaCarroll, Patrick J.Bacon, Alexandra M.Booth, Corwin H.Minasian, Stefan G.Autschbach, JochenZurek, EvaSchelter, Eric J.2024-04-172024-04-172024-04-172024-03-2710.1021/acsami.3c18766https://infoscience.epfl.ch/handle/20.500.14299/207306WOS:001192385500001Electron-rich organocerium complexes (C5Me4H)(3)Ce and [(C5Me5)(2)Ce(ortho-oxa)], with redox potentials E-1/2 = -0.82 V and E-1/2 = -0.86 V versus Fc/Fc(+), respectively, were reacted with fullerene (C-60) in different stoichiometries to obtain molecular materials. Structurally characterized cocrystals: [(C5Me4H)(3)Ce](2)<middle dot>C-60 (1) and [(C5Me5)(2)Ce(ortho-oxa)](3)<middle dot>C-60 (2) of C-60 with cerium-based, molecular rare earth precursors are reported for the first time. The extent of charge transfer in 1 and 2 was evaluated using a series of physical measurements: FT-IR, Raman, solid-state UV-vis-NIR spectroscopy, X-ray absorption near-edge structure (XANES) spectroscopy, and magnetic susceptibility measurements. The physical measurements indicate that 1 and 2 comprise the cerium(III) oxidation state, with formally neutral C-60 as a cocrystal in both cases. Pressure-dependent periodic density functional theory calculations were performed to study the electronic structure of 1. Inclusion of a Hubbard-U parameter removes Ce f states from the Fermi level, opens up a band gap, and stabilizes FM/AFM magnetic solutions that are isoenergetic because of the large distances between the Ce(III) cations. The electronic structure of this strongly correlated Mott insulator-type system is reminiscent of the well-studied Ce2O3.TechnologyMolecular MaterialsFullerideStrongly CorrelatedelectronsSpectroscopyMott InsulatorDensity Functional Theorytext::journal::journal article::research article