J. I. Flege,1,2,* Th. Schmidt,2 M. Siebert,2 G. Materlik,3 and J. Falta2 1Hamburger Synchrotronstrahlungslabor HASYLAB/DESY, Notkestrasse 85, 22603 Hamburg, Germany 2Institut für Festkörperphysik, Universität Bremen, Otto-Hahn-Allee 1, 28359 Bremen, Germany 3Diamond Light Source Limited, Diamond House, Chilton, Didcot, Oxfordshire OX11 0DE, United Kingdom Received 27 September 2007; revised man...

S. Meng, A. Bostwick, B.R. Schroeder, E. Rotenberg, F.S. Ohuchi, and M.A. Olmstead Department of Physics, University of Washington, Seattle, Washington 98195 USA Advanced Light Source, Ernest Orlando Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720 USA Department of Materials Science and Engineering, University of Washington, Seattle, Washington 98195 USA

As everyone knows, an atom is the smallest unit of a chemical element, and atoms combine to form molecules and solids. Each element is uniquely specified by its atomic number Z. However a given element may occur in several different versions, called isotopes; these have the same Z but different atomic mass number A. A glance at the periodic table shows that for the naturally occurring elements ...

We employ scanning probe microscopy to reveal atomic structures and nanoscale morphology of graphene-based electronic devices (i.e., a graphene sheet supported by an insulating silicon dioxide substrate) for the first time. Atomic resolution scanning tunneling microscopy images reveal the presence of a strong spatially dependent perturbation, which breaks the hexagonal lattice symmetry of the g...

Nitinol (NiTi), the most widely used shape-memory alloy, exhibits an austenite phase that has yet to be identified. The usually assumed austenitic structure is cubic B2, which has imaginary phonon modes, hence it is unstable. We suggest a stable austenitic structure that " on average " has B2 symmetry (observed by x-ray and neutron diffraction), but it exhibits finite atomic displacements from ...

A combined theoretical and experimental approach has been used to study nanoscale CoFe/Cu/CoFe multilayer films grown by sputter deposition. Such films have applications in sensors that utilize the giant magnetoresistance effect, for example, read heads in high-density information storage devices. Atomistic simulations based on a molecular dynamics approach and an alloy form of the embedded ato...

Despite the difficulties associated with determining atomic-level structures for materials that are fibrous, structural biologists are making headway in understanding the architecture of amyloid-like fibrils. It has long been recognized that these fibrils contain a cross-beta spine, with beta-strands perpendicular to the fibril axis. Recently, atomic structures have been determined for some of ...

Titania nanosheets are two-dimensional single crystallites of titanium oxide with a thickness of one titanium or two oxygen atoms, and they show attractive material properties, such as photocatalytic reactions. Since a titania (Ti₀.₈₇O₂) nanosheet is synthesized by the delamination of a parent layered K₀.₈Ti₁.₇₃Li₀.₂₇O₄ crystal using a soft chemical procedure, substantial Ti vacancies are expec...

Understanding the mechanism of nanoparticle formation during synthesis is a key prerequisite for the rational design and engineering of desirable materials properties, yet remains elusive due to the difficulty of studying structures at the nanoscale under real conditions. Here, the first comprehensive structural description of the formation of a nanoparticle, yttria-stabilized zirconia (YSZ), a...

Nitrogen atoms adsorbed on a Fe(100) surface cause the formation of an ordered ~(2x2) overlayer with coverage 0.5. A structure analysis was performed by comparing experimental LEED I-V spectra with the results of multiple scattering Todel calculations. The N atoms were found to occupy fourfold hollow sites, with their plane 0.27 A above the plane of the surface Fe atoms. In addition, nitrogen a...