Materials Literature
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The structure of the $(\sqrt{31}\times \sqrt{31})R\pm9^\circ$ reconstructed phase on sapphire (0001) surface is investigated by means of a simulation based on the energy minimization. The interaction between Al adatoms is described with the semi-empirical many-body Sutton-Chen potential, corrected for the charge trans…
Correlated ab-initio ground-state calculations, using relativistic energy-consistent pseudopotentials, are performed for six II-VI semiconductors. Valence ($ns,np$) correlations are evaluated using the coupled cluster approach with single and double excitations. An incremental scheme is applied based on correlation co…
The free energies of vacancy pair formation and migration in MgO were computed via molecular dynamics using free-energy integrations and a non-empirical ionic model with no adjustable parameters. The intrinsic diffusion constant for MgO was obtained at pressures from 0 to 140 GPa and temperatures from 1000 to 5000 K.…
This book deals with the electron density distribution in molecules and solids as obtained experimentally by X-ray diffraction. It is a comprehensive treatment of the methods involved, and the interpretation of the experimental results in terms of chemical bonding and intermolecular interactions. Inorganic and organic…
We have developed methods for obtaining and characterizing three-dimensional maps of the reciprocal-space distribution of diffuse x-ray scattering from protein crystals, and have used the methods to study the nature of disorder in crystals of Staphylococcal nuclease. Experimentally obtained maps are 99.5% complete in…
The characterization of protein-folding kinetics with increasing chain length under various thermodynamic conditions is addressed using the capillarity picture in which distinct spatial regions of the protein are imagined to be folded or trapped and separated by interfaces. The quantitative capillarity theory is based…
L-Asparaginyl and L-aspartyl residues in proteins are subject to spontaneous degradation reactions that generate isomerized and racemized aspartyl derivatives. Proteins containing L-isoaspartyl and D-aspartyl residues can have altered structures and diminished biological activity. These residues are recognized by a hi…
First principles calculations show that chemisorbed H causes vacancy reconstructions and faceting of all Al low index surfaces. On Al(111) H-decorated vacancies are stable; on H-covered Al(100) vacancies are easily activated thermally. H-covered Al(110) forms a missing row reconstruction with H-decorated vacancies on…
Atomic-force microscopy measurements on KDP ${101}$ faces are presented which show that the terrace width $W$ on vicinal dislocation growth hillocks is nearly independent of supersaturation \ensuremath{\sigma} and Burgers vector $b$, in contradiction to simple Burton-Cabrera-Frank models. An analytical model taking in…
Large-scale integrated fabrication in a H2 containing atmosphere, for example, during the passivation process, can cause serious damage in metal/Pb(Zr,Ti)O3/metal capacitors (i.e., Pt/PZT/Pt capacitors). To reveal the cause of the H2 damage, we investigated the behavior of hysteresis curves and the leakage current of…
We report on quantum molecular dynamics simulations of ${\mathrm{C}}_{28}$ deposition on a semiconducting surface. Our results show that under certain deposition conditions ${\mathrm{C}}_{28}$'s act as building blocks on a nanometer scale to form a thin film of nearly defect-free molecules. The ${\mathrm{C}}_{28}$'s b…
Raman scattering in ${\mathrm{Ge}}_{x}{X}_{1\ensuremath{-}x}$ glasses, $X\phantom{\rule{0ex}{0ex}}=\phantom{\rule{0ex}{0ex}}\mathrm{S}$ or Se, reveals that the frequency of ${A}_{1}$ modes of corner-sharing $\mathrm{Ge}({X}_{1/2}{)}_{4}$ tetrahedra displays a discontinuous jump between $x\phantom{\rule{0ex}{0ex}}=\pha…
Raman scattering spectra of single-wall nanotubes with mean radii 0.55, 0.65, and 1.0 nm show size-dependent multiple splittings of the optical phonon peak corresponding to the ${E}_{2g}$ mode in graphite. These splittings constitute the first experimental evidence for the unique feature of nanotubes that they exhibit…
The contribution from the irreversible displacement of non- domain walls to the direct longitudinal piezoelectric coefficient of and ceramics was determined quantitatively by using the Rayleigh law. Effects of the crystal structure and microstructure of the ceramics as well as the external d.c. pressure on the domain…
An extremely large magnetic entropy change has been discovered in $\mathrm{Gd}{}_{5}(\mathrm{Si}{}_{2}\mathrm{Ge}{}_{2})$ when subjected to a change in the magnetic field. It exceeds the reversible (with respect to an alternating magnetic field) magnetocaloric effect in any known magnetic material by at least a factor…
The resonance Raman spectrum of InP nanocrystals is characterized by features ascribable to both longitudinal (LO) and transverse (TO) optical modes. The intensity ratio of these modes exhibits a strong size dependence. To calculate the size dependence of the LO and TO Raman cross sections, we combine existing models…
The phase behavior of fluid mixtures of hard uniaxial ellipsoids with elongations e and 1/e, and equal molecular volume, has been studied using constant-pressure Gibbs ensemble Monte Carlo simulations for e=15 and e=20. Four distinct phases are observed: isotropic (I), uniaxial nematic (N+ and N−) and biaxial nematic…
This review concerns the experimental and theoretical publications devoted to the important problem of the large piezoelectric anisotropy in -based polarized ferroelectric ceramics.
The dielectric properties of biaxially stretched polyethylene terephthalate (PET) films of thickness and 68% degree of crystallinity were investigated by means of dielectric relaxation spectroscopy in the frequency range Hz and the temperature range C. Differencial scanning calorimetry (DSC), in the range C, was emplo…
A beam with piezoceramic elements bonded to the beam's top and bottom surfaces is investigated. Simple pin-force models allow the user to predict the deformation of the beam very well for the static case. As the pin-force models are simple they are well suited for active control algorithms of such structures. In exper…