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A conventional solution-based route to a cyclic trimeric organozinc compound [{Zn(Et)( β-diketonate)}3] ( β-diketonate=OC(OMe)CHC(Me)O, 1) is described, with 1 structurally characterized for the first time. The ligand selection of bidentate β-diketonates is shown to be key to isolating a cyclic trimer. Additional reaction of β-diketonates with diethyl zinc were spectroscopically characterized as compounds of the type [{Zn(Et)( β-diketonate)} n] ( β-diketonate=OC(Me)CHC(Me)O, 2, OC(O tBu)CHC(Me)O, 3). Further studies have shown that selective oxidation of these species produces cubanes of the general formula [{Zn(OC(R)CHC(Me)O)2Zn(Et)OEt}2] (R=OMe, 4; Me, 5; O tBu, 6), allowing a high oxygen content whilst remaining structurally suitable for use as precursors. The successful deposition of thin films of zinc oxide through aerosol-assisted chemical vapor deposition (AACVD), using a novel precursor, is described and fully characterized. [ABSTRACT FROM AUTHOR]

Aerosol-assisted chemical vapour deposition (AACVD) reactions of GaMe3, ZnEt2 and the donor-functionalised alcohol HOCH2CH2OMe (6 equiv.) in toluene resulted in the deposition of amorphous transparent zinc gallate (ZnGa2O4) films at a range of temperatures (350-550 °C). The zinc-gallium oxide films were analyzed by scanning electron microscopy, X-ray photoelectron spectroscopy (XPS), energy-dispersive X-ray analysis, glancing-angle X-ray powder diffraction (XRD) and optical studies. The optimum growth temperature was found to be 450 °C, which produced transparent films with excellent coverage of the substrate. XPS confirmed the presence of zinc, gallium and oxygen in the films. Annealing these films at 1000 °C resulted in crystalline films and glancing-angle powder XRD showed that a zinc gallate spinel framework with a lattice parameter of a=8.336(5) Å was adopted. [ABSTRACT FROM AUTHOR]

Highly transparent (>85 %) and conductive (1.086×10−3 Ω cm) zinc oxide thin films have been deposited from specifically selected precursors allowing us to establish a direct correlation between their molecular structure and the optoelectronic properties of the deposited films. Mono‐ligated ethyl zinc compounds of varying steric bulk: [EtZn(OC(Me)CH(Me)N(iPr))]2 (1), [EtZn(OC(OEt)CH(Me)N(iPr))]2 (2) and [EtZn(OC(OEt)CH(CH3)N(Dipp))]2 (3) were compared with the related bis‐ligated zinc complexes [Zn(OC(Me)CH(Me)N(iPr))2] (4), [Zn(OC(OEt)CH(Me)N(iPr))2] (5) and [Zn(OC(OEt)CH(Me)N(Dipp))2] (6). In all cases bulkier ligands resulted in poorer electronic properties of deposited films, whilst all mono‐ligated compounds were shown as superior precursors. All complexes were characterised by 1H and 13C{1H} NMR and elemental analysis, with the structure of 6 determined by single crystal X‐ray diffraction. Zinc oxide films were deposited from single and dual source (with methanol) reactions of these precursors, and analysed via XRD, XPS and EDX. Optoelectronic properties were investigated through UV/vis spectroscopy and Hall effect measurements, and morphology was examined via SEM. Tauc plots from UV/vis data indicated that Film A showed the lowest band gap of 3.31 eV. Varying the elemental composition of the precursors led to changes in the elemental composition of the resultant films, as well as changes in their structural and optoelectronic properties. Using this approach of precursor design, we have been able to tune single source precursors towards zinc oxide to deposit films with specific properties. [ABSTRACT FROM AUTHOR]

A set of heteroleptic ethyl zinc β-amidoenoates (1, 2) and β-ketoiminates (3) of the form [LZnEt]2 with varying steric bulk have been synthesised via the reaction of diethylzinc with β-aminoenoate ligands HL1 and HL2 and β-ketoimine HL3. These complexes have been characterised via 1H and 13C NMR, mass spectrometry and single-crystal X-ray diffraction, which unambiguously determined all three structures as dimeric species in the solid state. We observe the unusual dimerisation of 1 and 2 through coordination of the central zinc atom to the methine carbon of the second monomer, which gives these complexes high reactivity. The thermal properties of complex 3 are explored via thermal gravimetric analysis (TGA), to investigate their potential as single-source precursors to zinc oxide, which shows that 3 has a significantly lower decomposition temperature as compared to its bis-ligated counterpart [Zn(L3)2], which gives 3 promise as a single-source precursor to zinc oxide. [ABSTRACT FROM AUTHOR]