Synthetic routes to a nanoscale inorganic cluster [Ga{sub 13}(μ{sub 3}-OH){sub 6}(μ{sub 2}-OH){sub 18}(H{sub 2}O)](NO{sub 3}){sub 15} evaluated by solid-state {sup 71}Ga NMR

• Published in: Journal of solid state chemistry Vol. 242; no. Part 2
• Main Authors: Hammann, Blake A., Marsh, David A., Ma, Zayd L., Wood, Suzannah R., Eric West, Michael, Johnson, Darren W., Hayes, Sophia E.
• Format: Journal Article
• Language: English
• Published: United States 15.10.2016
• Subjects: AMORPHOUS STATE; EXPERIMENTAL DATA; GALLIUM 71; IMPURITIES; INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; MATERIALS SCIENCE; MOLECULAR CLUSTERS; NANOSTRUCTURES; NITRATES; NITROGEN OXIDES; NMR SPECTRA; NUCLEAR MAGNETIC RESONANCE; RAMAN SPECTROSCOPY; THIN FILMS
• ISSN: 0022-4596; 1095-726X
• DOI: 10.1016/J.JSSC.2016.02.043

Solid-state {sup 71}Ga NMR was used to characterize a series of [Ga{sub 13}(μ{sub 3}-OH){sub 6}(μ{sub 2}-OH){sub 18}(H{sub 2}O)](NO{sub 3}){sub 15} “Ga{sub 13}” molecular clusters synthesized by multiple methods. These molecular clusters are precursors to thin film electronics and may be employed in energy applications. The synthetic routes provide varying levels of impurities in the solid phase, and these impurities often elude traditional characterization techniques such as powder X-ray diffraction and Raman spectroscopy. Solid-state NMR can provide a window into the gallium species even in amorphous phases. This information is vital in order to prevent the impurities from causing defect sites in the corresponding thin films upon gelation and condensation (polymerization) of the Ga{sub 13} clusters. This work demonstrates the resolving power of solid-state NMR to evaluate structure and synthetic quality in the solid state, and the application of high-field NMR to study quadrupolar species, such as {sup 71}Ga. - Graphical abstract: The various synthetic routes and {sup 71}Ga solid-state NMR spectra of the nanoscale inorganic cluster [Ga{sub 13}(μ{sub 3}-OH){sub 6}(μ{sub 2}-OH){sub 18}(H{sub 2}O)](NO{sub 3}){sub 15}. - Highlights: • Solid-state {sup 71}Ga NMR of hydroxo-aquo metal clusters and the impurities present. • High-field NMR capability allows for quadrupolar species, such as {sup 71}Ga, to be routinely studied. • Efficient and environmentally friendly synthetic routes have been developed to prepare hydroxo-aquo metal clusters.