Materials Literature
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An iterative process for improving the completeness and quality of atomic models automatically built at moderate resolution (up to about 2.8 A) is described. The process consists of cycles of model building interspersed with cycles of refinement and combining phase information from the model with experimental phase in…
We present the crystallization kinetics for two polydisperse hard-sphere particle stocks with differing particle size distributions. One of the latexes had a relatively symmetrical distribution, the other had a more polydisperse distribution, which was highly skewed to smaller sizes. The emerging Bragg reflections fro…
The Raman scattering on acoustical phonons from ${\mathrm{CdS}}_{x}{\mathrm{Se}}_{1\ensuremath{-}x}$ quantum dots in a glass matrix were investigated for in- and off-resonance conditions. By a comparison with a model calculation, the off-resonance scattering showed that the homogeneous broadening mainly contributes to…
Aluminosilicate MCM-48 materials with Si/Al ratio between 4 and 50 were prepared via direct mixed-gel synthesis, and their hydrothermal stability in boiling water and steam was investigated using a variety of techniques including powder XRD, N 2 sorption studies, and elemental analysis. The stability of Al-containing…
Effects of solvent exchange and milling on the solid structure of cellulose were investigated, using small- and wide-angle X-ray scattering and solid-state NMR. The solvent exchange facilitated the dissolution of cellulose in LiCl/DMAc with no change of the crystalline structure of cellulose. In contrast, the milling…
The nucleation event in protein crystallization is a part of the process that is poorly controlled. It is generally accepted that the protein should be in the metastable phase for crystal growth, but for nucleation higher levels of saturation are needed. Formation of nuclei in bulk solvent requires interaction of prot…
The geometries of neutral and charged carbon single-walled nanotubes (SWNTs) have been calculated using density functional theory. Periodic boundary conditions, a plane wave basis, and ultrasoft pseudopotentials are used in the generalized gradient approximation for isolated SWNTs with diameters of up to 20 and 12.5 Å…
A systematic experimental study of polymer-induced changes of the collective structure of model hard-sphere nanocolloids in the fluid and gel states has been carried out using ultra-small-angle x-ray scattering. The focus is on small, non-adsorbing polymer depletants where a direct transition from the homogeneous flui…
The effects of sulfur on the adhesion of ${\mathrm{N}\mathrm{i}/\mathrm{A}\mathrm{l}}_{2}{\mathrm{O}}_{3}$ interfaces are determined from first principles. The interfacial bonding is analyzed in terms of its ionic, covalent, and metallic components as well as its local electron orbital symmetries. The results reveal t…
The ET dynamics of a series of donor-spacer-acceptor (D-Sp-A) systems featuring (porphinato)zinc(II), (aryl)ethynyl bridge, and arene diimide units were investigated by pump-probe transient absorption spectroscopy. Analysis of these data within the context of the Marcus-Levich-Jortner equation suggests that the pi-con…
We report x-ray magnetic linear dichroism (XMLD) measurements at the Fe ${L}_{2,3}$ absorption edges of thin antiferromagnetic (AFM) ${\mathrm{LaFeO}}_{3}$ films grown epitaxially on ${\mathrm{SrTiO}}_{3}$ (100) and (110) substrates and a stepped (100) substrate with a 2\ifmmode^\circ\else\textdegree\fi{} miscut. The…
High-frequency and -field electron paramagnetic resonance (HFEPR) spectroscopy of a classical coordination complex, Mn(acac)(3) (Hacac = 2,4-pentanedione), has been performed on both solid powder and frozen solution (in CH(2)Cl(2)/toluene, 3:2 v/v) samples. Parallel mode detection X-band EPR spectra exhibiting resolve…
A new method and the software program BEST for optimal planning of X-ray data collection from protein crystals using the rotation method are presented. From one or a few initial diffraction images, BEST estimates the statistical characteristics of the data set for different combinations of data-collection parameters a…
An in situ x-ray diffraction experiment has been performed on phosphorus to characterize the liquid-liquid transition which occurs at high temperature and pressure. The transition line has been measured over an extended temperature range up to 2200 degrees C at 0.3 GPa. From the shape of this line, a thermodynamic cha…
Two oxygen species, which are constituents of the active centers for ethylene epoxidation over silver, have been characterized by a number of physical methods sensitive to adsorbate electronic structure such as x-ray photoelectron, ultraviolet photoelectron, Auger, and x-ray-absorption near-edge structure spectroscopy…
Dye doping is a promising way to increase the spectral purity of polymer light-emitting diodes (LEDs). Here we analyze the frequency and field dependence of the complex admittance of Al-Ba-PPV-PEDOT-ITO LEDs with and without dye. We compare the charge carrier mobilities of pristine and dye-doped double-carrier and hol…
The asymptotic analysis of the radiation pattern of a classical dipole in a photonic crystal possessing an incomplete photonic bandgap is presented. The far-field radiation pattern demonstrates a strong modification with respect to the dipole radiation pattern in vacuum. Radiated power is suppressed in the direction o…
The second order (in time) Schrodinger equation is proposed. The additional term (in comparison to Schrodinger equation) describes the interaction of particles with vacuum filled with virtual particle-antiparticle pairs (zitterbewegung). Key words: Schrodinger equation; Nanoscience; Zitterbewegung.
In this paper the Boltzmann transport equation for thermal processes induced by ultra-short laser pulses is formulated and solved. For thermal process where the duration of the laser pulse (femtoseconds - attoseconds) is shorter than the relaxation time, the solution of Boltzmann equation differs from the solution of…
The morphological evolution of the inorganic crystals (Ba(NO 3 ) 2, NH 4 Cl, H 3 BO 3, and K 2 Cr 2 O 7 ) was demonstrated in various kinds of organic gel media (agar, gelatin, pectin, and poly (vinyl alcohol)). As the gel density increased, the morphology grown in the gel matrix remarkably changed from polyhedral sin…