The analysis of transparent conducting oxide nanostructures suffers from a lack of high throughput yet quantitatively sensitive set of analytical techniques that can properly assess their electrical properties and serve both as characterization and diagnosis tools. This is addressed by applying a comprehensive set of characterization techniques to study the electrical properties of solution-grown Al-doped ZnO nanowires as a function of composition from 0 to 4 at. % Al:Zn. Carrier mobility and charge density extracted from sensitive optical absorption measurements are in agreement with those extracted from single-wire field-effect transistor devices. The mobility in undoped nanowires is 28 cm 2 / V s and decreases to ϳ14 cm 2 / V s at the highest doping density, though the carrier density remains approximately constant ͑10 20 cm −3 ͒ due to limited dopant activation or the creation of charge-compensating defects. Additionally, the local geometry of the Al dopant is studied by nuclear magnetic resonance, showing the occupation of a variety of dopant sites.

We present the results of a variable-temperature (VT) 31 P magic angle spinning NMR (MAS-NMR) study of a series of solid solutions between different synthetic rare earth (RE = Y, La, Ce, Pr, Nd, Eu, Dy) orthophosphates (REPO 4 ) taking either the monoclinic monazite or tetragonal xenotime (zircon) crystal structure. Solid solutions were formed by mixing a small amount of a paramagnetic REPO 4 material (RE = Ce, Pr, Nd, Eu, Dy) with either diamagnetic LaPO 4 or YPO 4 , which take the monoclinic and tetragonal crystal structures, respectively. Mixtures were made with up to 10 mol% (nominal content) of the paramagnetic component. 31 P spectra of these materials contained several paramagnetically shifted resonances indicating some dissolution of the paramagnetic rare earth into the host LaPO 4 or YPO 4 phase; however, it is clear that none of the samples studied here reached a state of complete solid solution. The use of multiple paramagnetic species in dilute solid solution with two diamagnetic materials taking different crystal structures enabled an investigation of the probable mechanisms of paramagnetic interactions in the 31 P NMR experiments. A peak assignment model is introduced for the 31 P spectra. Our analysis indicates that the paramagnetic interactions are dominated by the Fermi contact shift with a secondary contribution from the so-called "pseudocontact" shift.

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Trace element chemistry was collected over the course of several years at GIA using two different laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) systems. The ICP-MS used was either a Thermo Fisher X-Series II or iCAP

G arnets are a group of isometric nesosilicates with the general chemical formula X 3 Y 2 Z 3 O 12. X, Y, and Z represent dodecahedral, octahedral, and tetrahedral sites in the crystal structure, respectively. Natural rock-forming silicate garnets with the Z-site occupied by Si 4+ are commonly divided into the pyralspite and ugrandite groups. In pyralspite, Al 3+ occupies the Y-site and the X-site may contain Mg 2+ , Fe 2+ , or Mn 2+ ; these garnets are dominantly composed of the pyrope (Mg 3 Al 2 Si 3 O 12), almandine (Fe 2+ 3 Al 2 Si 3 O 12), and spessartine (Mn 3 Al 2 Si 3 O 12) end members. The ugrandite garnets have Ca 2+ on the X-site and Cr 3+ , Al 3+ , or Fe 3+ on the Y-site, giving uvarovite (Ca 3 Cr 2 Si 3 O 12), grossular (Ca 3 Al 2 Si 3 O 12), or andradite (Ca 3 Fe 2 3+ Si 3 O 12) end members. Stockton and Manson (1985) proposed a classification scheme for separating the pyralspite group into the gemological species of pyrope, almandine, spessartine, pyrope-almandine, pyrope-spessartine, and almandine-spessartine. Previously, two types of color-change garnets have been reported: pyrope with very high Cr 3+ (