111 research outputs found
Surface Structure of Liquid Metals and the Effect of Capillary Waves: X-ray Studies on Liquid Indium
We report x-ray reflectivity (XR) and small angle off-specular diffuse
scattering (DS) measurements from the surface of liquid Indium close to its
melting point of C. From the XR measurements we extract the surface
structure factor convolved with fluctuations in the height of the liquid
surface. We present a model to describe DS that takes into account the surface
structure factor, thermally excited capillary waves and the experimental
resolution. The experimentally determined DS follows this model with no
adjustable parameters, allowing the surface structure factor to be deconvolved
from the thermally excited height fluctuations. The resulting local electron
density profile displays exponentially decaying surface induced layering
similar to that previously reported for Ga and Hg. We compare the details of
the local electron density profiles of liquid In, which is a nearly free
electron metal, and liquid Ga, which is considerably more covalent and shows
directional bonding in the melt. The oscillatory density profiles have
comparable amplitudes in both metals, but surface layering decays over a length
scale of \AA for In and \AA for Ga. Upon controlled
exposure to oxygen, no oxide monolayer is formed on the liquid In surface,
unlike the passivating film formed on liquid Gallium.Comment: 9 pages, 5 figures; submitted to Phys. Rev.
Surface-roughness fractality effects in electrical conductivity of single metallic and semiconducting films
Reactions of an aromatic σ,σ-biradical with amino acids and dipeptides in the gas phase
WN/sub x/ diodes on plasma-treated GaAs surfaces
The formation of WNx Schottky diodes on GaAs surfaces with various interface conditions was investigated by performing H2- and N2-plasma treatments on GaAs surfaces prior to the WNx film deposition. After annealing at 810 degrees C for 10 min, an improvement in the diode rectifying characteristics was generally observed, resulting from the thermal recovery of the sputtering and plasma-induced damage. The maximum Phi I-V=0.76 eV was obtained for the H2-plasma-treated diodes. Samples with an N2-plasma-treated interface showed a reduced barrier height and a higher ideality factor with corresponding nonlinearity in the C-V curves due to the presence of a high density of interfacial states
Recommended from our members
Reduction of Weinreb amides to aldehydes under ambient conditions with magnesium borohydride reagents Dedicated to the memory of Professor Sheldon Shore
Chloromagnesium dimethylaminoborohydride (ClMg+ [H3BNMe2]-, MgAB) is an analogue of the versatile lithium dialkylaminoborohydrides (LAB reagents), prepared by the reaction of dimethylamine-borane with methylmagnesium chloride. MgAB is a partial reducing agent for Weinreb amides under ambient conditions and is complementary to the commonly utilized lithium aluminum hydride (LiAlH4) and diisobutylaluminum hydride (DIBAL) reagents, while exhibiting enhanced chemoselectivity. To prevent over-reduction, the aldehyde products are readily isolated in good yields by forming the sodium bisulfite adducts. Aldehyde products can both be stored and later used as the bisulfite adducts, or can be regenerated from the bisulfite adducts by treatment with aqueous formaldehyde
- …