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The first magnetic structure determination of a fullerene-based molecular ferromagnet by powder neutron diffraction is provided. The lanthanide exchange interactions in Eu(sub 6)C(sub 60) are modulated by the C(sub 60) anions and orbital mixing can account for the observed magnetic and conducting properties of the material.

The authors have measured pulse shapes (pulse height and rise time) in diode- and Ohmic-type CdTe x-ray detectors in order to investigate the polarization phenomena observed in diode-type detectors. Using α particles incident on either cathode or anode side, they can independently focus on electron or hole movement. The authors find that the carrier movements are different between the two types of detectors. This implies that, in the diode-type detectors, electrons are trapped in the vicinity of the In electrode (anode), while holes are trapped and detrapped throughout the CdTe crystal or in the vicinity of the Pt electrode (cathode). [ABSTRACT FROM AUTHOR]

The three-dimensional atomic configuration of amorphous Ge2Sb2Te5 and GeTe were derived by reverse Monte Carlo simulation with synchrotron-radiation x-ray diffraction data. The authors found that amorphous Ge2Sb2Te5 can be regarded as “even-numbered ring structure,” because the ring statistics is dominated by four- and six-fold rings analogous to the crystal phase. On the other hand, the formation of Ge–Ge homopolar bonds in amorphous GeTe constructs both odd- and even-numbered rings. They believe that the unusual ring statistics of amorphous Ge2Sb2Te5 is the key for the fast crystallization speed of the material. [ABSTRACT FROM AUTHOR]

A method has been developed for analyzing the structure of crystalline nanowires deposited on a crystal surface. It combined in-air grazing-incidence surface scattering with high-energy synchrotron x-ray scattering. The technique has allowed a direct reciprocal-lattice space mapping of the x-ray intensities scattered from ultrathin nanowires. Using this method, the sheet-shape diffraction emanating from ultrathin NiO wires was observed. The average nanowire–nanowire distance of 46 nm and a crystallographic domain size of approximately 7.5 nm across the nanowire were evaluated. © 2004 American Institute of Physics. [ABSTRACT FROM AUTHOR]

We have measured the local current density on individual single-wall carbon nanotubes (SWNTs) with the conducting tip of an atomic force microscope; the SWNTs make up a nanometer-scale electronic circuit on an insulating substrate. Scanning tunneling spectroscopy measurements at certain positions on a SWNT bundle show that both metallic and semiconducting nanotubes can coexist in a bundle. The approach applied in this experiment appears as a powerful technique for the investigation of the spatial variation of current density and electronic states of nanometer-scale electronic devices. [ABSTRACT FROM AUTHOR]