We report tip-enhanced and conventional Raman spectroscopy studies of Ge-Si0.5Ge0.5 core-shell nanowires in which we observe two distinct Ge-Ge vibrational mode Raman peaks associated with vibrations in the Ge nanowire core and at the Ge-Si0.5Ge0.5 interface at which a quantum-confined hole gas is formed. Tip enhanced Raman measurements show dramatically increased sensitivity to the modes at th...

Isotope clusters in library electron ionization mass spectra of germanes often appear a few u lower than theoretically expected from elemental composition; for example, the dominant peak of the Ge(4)H(10)(+) pattern is shifted 8 u down. This phenomenon is due to combinations of three essential components: the molecular ion Ge(n)H(2n+2)(+) and two products of hydrogen elimination, Ge(n)H(+) and ...

We report the synthesis, characterization, and computational rationalization of the first trimetallic deltahedral Zintl ions. The novel nine-atom clusters were structurally characterized as dimers of [(Sn(6)Ge(2)Bi)(2)](4-) with Ge-Ge intercluster bonds. They are synthesized either by reacting bimetallic clusters (Sn(9-x)Ge(x))(4-) with BiPh(3) or by direct extraction from precursors with nomin...

Morphological evolution of cobalt germanide epilayers, CoxGey, was investigated in situ by scanning tunneling microscopy and spectroscopy and reflection high-energy electron diffraction, as a function of deposition method and, hence, the phase content of the epilayer. During reactive deposition epitaxy, in which Co atoms were evaporated onto a flat pseudomorphic Ge/Si(001) wetting layer at 773 ...

By using the first-principles density functional theory, we calculate the partial charge densities and STM images for the intradimer di-σ and interdimer end-bridge adsorption configurations of ethylene on Ge(001). Our simulated STM images show the effects of ethylene adsorption and clarify that, although STM images and surface structures evolve as the adsorption sites of ethylene on Ge(001), th...

We develop and estimate a discrete-choice model of differentiated products for the corn and soybean seed industry in the United States to assess the welfare impact of genetically engineered (GE) crop varieties. We use a unique dataset, spanning the period 1996-2011, that contains rich information on the adoption of GE traits. Using a two-level nested logit model, we estimate that U.S. farmers a...

Introduction MOSFETs with a high-mobility channel are attractive candidates for advanced CMOS device structures, since it is becoming increasingly difficult to enhance Si CMOS performance through traditional device scaling. The lower effective mass and higher mobility of carriers in germanium (Ge) compared with silicon (Si) (2x higher mobility for electrons and 4x for holes) has prompted renewe...

OBJECTIVES To assess occupational exposure to inorganic germanium (Ge) in workers from a producing plant, and to assess the health of these workers, with a special focus on respiratory, kidney, and liver functions. METHODS Cross sectional study of 75 workers exposed to Ge and 79 matched referents. Exposure was characterised by measuring air and urine concentrations of the element during a typ...