title: Synthesis and characterization of a neutral titanium tris(iminosemiquinone) complex featuring redox-active ligands.
abstract: The neutral tris(semiquinonate) complex [Ti(dmp-BIAN(isq))(3)] [dmp-BIAN(isq) = N,N'-bis(3,5-dimethylphenylimino)acenaphthenesemiquinonate] was structurally, spectroscopically, and electrochemically characterized. Solid-state magnetism experiments reveal field-quenchable, enhanced temperature-independent paramagnetism (TIP). Density functional theory calculations employing the experimental geometry predicts a strong antiferromagnetic coupling, leading to an S = 0 ground state, but they also hint at spin frustration and concomitant close-lying, excited states, which cause the observed large TIP by admixture into the ground state. The dmp-BIAN(isq) ligand, which facilitates intramolecular electron transfer, was shown to undergo four quasi-reversible redox processes, demonstrating the ability of the ligand to act as an electron reservoir in complexes of early metals.
authors: Department of Chemistry, University of California, Irvine, California 92697, USA. kmclark@uci.edu
authors: Kensha Marie
authors: KM
authors: Clark
authors: Jesper
authors: J
authors: Bendix
authors: Alan F
authors: AF
authors: Heyduk
authors: Joseph W
authors: JW
authors: Ziller
mesh_terms: D008024:Ligands; D008958:Models, Molecular; D015394:Molecular Structure; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry*; D010084:Oxidation-Reduction; D011789:Quantum Theory; D011809:Quinones / Q000737:chemistry*; D014025:Titanium / Q000737:chemistry*
chemical_list: D008024:Ligands; D009942:Organometallic Compounds; D011809:Quinones; C576291:titanium(N,N'-bis(3,5-dimethylphenylimino)acenaphthenesemiquinonate)3; D014025:Titanium