Synthesis and Characterization of Germanium Coordination Compounds for Production of Germanium Nanomaterials

A series of novel germanium(II) precursors was synthesized to initiate an investigation between the precursors' structures and the morphologies of the resulting nanoparticles. Theprecursors were synthesized from the reaction of Ge[N(SiMe3)2]2 or [Ge(OtBu)2]2 and the appropriate ligand: N,N″‐dibenzylethylenediamine (H2‐DBED), tert‐butyl alcohol (H‐OtBu), 2,6‐dimethylphenol (H‐DMP), 2,6‐diphenylphenol (H‐DPP), tert‐butyldimethylsilanol (H‐DMBS), triphenylsilanol (H‐TPS), triphenylsilanethiol (H‐TPST), and benzenethiol (H‐PS). The products were identified as: [Ge(μc‐DBED)]2 (1, μc = bridging chelating), [Ge(μ‐DMP)(DMP)]2 (2), Ge(DPP)2 (3), [Ge(μ‐OtBu)(DMBS)]2, (4), [Ge(μ‐DMBS)(DMBS)]2 (5), Ge(TPS)3(H) (6), [Ge(μ‐TPST)(TPST)]2 (7), and Ge(PS)4 (8). The GeII metal centers were found to adopt a pyramidal geometry for 1, 2, 4, 5, 7, a bent arrangement for 3, and a tetrahedral coordination for the GeIV species 6 and 8. Using a simple solution precipitation methodology, Ge0 nanomaterials were isolated as dots and wires for the majority of precursors. Compound 7 led to the isolation of amorphous GexSy. The nanomaterials isolated were characterized by TEM, EDS, and powder XRD. A correlation between the precursor's arrangement and final observed nanomorphology was proffered as part of the “precursor structure affect” phenomenon. (© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2009)