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A series of homoleptic complexes with non-innocent ligands derived from N,N′-bis(pentafluorophenyl)-o-phenylenediamine (H2Fpda) are reported. [NiII(Fsbqdi)2] (1), [PdII(Fsbqdi)2] (2), [CoII(Fsbqdi)2] (3), and [CuII(Fsbqdi)2] (4) were synthesized, where (Fsbqdi)1− represents a radical anion formed by one-electron oxidation of the doubly deprotonated H2Fpda. The oxidation states of ligands and metals in complexes 1–4 were assigned by single crystal X-ray crystallography performed at low temperatures. Complex 4 is the first CuII complex where both o-phenylenediamine derived ligands are monoanionic radicals. The bulky N–C6F5 substituents force the complexes 1, 3, and 4 to adopt a twisted geometry (intermediate between square-planar and tetrahedral). The electronic structures of the neutral compounds 1–4 and of some of their cationic and/or anionic neighboring redox states were probed using EPR and UV-VIS-NIR spectroelectrochemistry. The twisted geometry of the complexes results in considerable changes in their electronic structures compared to the well known square-planar complexes while the strongly electron withdrawing N-C6F5 groups have a great influence on redox properties. [ABSTRACT FROM AUTHOR]

Mn5Ge3 can be used as a ferromagnetic contact material to fabricate spintronic devices. Here, we show that Mn5Ge3 can be fabricated with a simple germanidation process by evaporating Mn on undoped and doped Ge on Si followed by a thermal annealing step to form the ferromagnetic Mn5Ge3 phase. This solid phase preparation of Mn5Ge3 is a robust process with a minor dependence on the annealing parameters. The formation of Mn5Ge3 can be realized using undoped as well as highly doped p-Ge and n-Ge with different doping levels. The interface of Mn5Ge3 is atomically sharp which leads to very low contact resistivities < 1 × 10−7 Ω cm2. [ABSTRACT FROM AUTHOR]