| Abstract
| - Three novel Zn(hfa)2·2H2O·polyether adducts have been prepared through simple procedures with stoichiometric quantities of zinc hydroxide, Hhfa, and polyether. The productshave been characterized by elemental analysis, X-ray single-crystal analysis, fast atombombardment mass spectra, 1H and 19F NMR spectra, thermogravimetric (TG)−differentialTG−differential scanning calorimetry (DSC) thermal measurements, and infrared transmittance spectroscopy. An attempt to obtain water-free adduct was unsuccessful even usingexcess polyethers. X-ray single-crystal data of the Zn(hfa)2·2H2O·diglyme adduct show thatthe polyether does not coordinate to the metal center. Nevertheless, metrical data areindicative of bridging interactions involving the oxygen of one coordinated H2O moleculeand the three oxygens of the diglyme. Very mild heating (37−51 °C) results in liquidcompounds that, in turn, can easily be evaporated. Preliminary gas-phase Fourier transform-IR measurements in vacuo suggest that the anhydrous Zn(hfa)2·diglyme forms uponevaporation due to competing H2O and diglyme ancillary ligation. Deposition experiments,in a low-pressure horizontal hot-wall reactor, on fused SiO2 (quartz) substrates, result inZnO films. X-ray diffraction measurements provide evidence that they consist of hexagonal(002) and (10l) oriented, crystals. UV−vis spectra show that the transmittance of as depositedfilms in the visible region is about 90%.
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