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The glass transition is the freezing of a liquid into a solid state without evident structural order. Although glassy materials are well characterized experimentally, the existence of a phase transition into the glass state remains controversial Here, we present numerical evidence for the existence of a novel first-order dynamical phase transition in atomistic models of structural glass formers. In contrast to equilibrium phase transitions, which occur in configuration space, this transition occurs in trajectory space, and it is controlled by variables that drive the system out of equilibrium. Coexistence is established between an ergodic phase with finite relaxation time and a nonergodic phase of immobile molecular configurations. Thus, we connect the glass transition to a true phase transition, offering the possibility of a unified picture of glassy phenomena.

Ultralong beltlike (or ribbonlike) nanostructures (so-called nanobelts) were successfully synthesized for semiconducting oxides of zinc, tin, indium, cadmium, and gallium by simply evaporating the desired commercial metal oxide powders at [...]

M. Zhang and P. Boolchand argue that properties of the glassy state in systems like Si[O.sub.2] and [([Na.sub.2]O).sub.χ] [(Te[O.sub.2]).sub.1-χ] can be understood in terms of a constrained network picture (1). [...]

One of the early triumphs of surface science was an explanation for the p(4x4) diffraction pattern observed when oxygen was adsorbed on the closest packed (111) surface of silver. In [...]

Manganese oxides are used in batteries, chemical separation, and catalysis because of their porosity, acidity, and ion exchange properties. Organic templates have been used to make complex architectures but require [...]

High-valent metal-oxo compounds are often used to mediate or catalyze oxidations of organic substrates. Nolin et al. have pursued the counterintuitive approach of using a rhenium-oxo complex to catalyze reduction. [...]

Oxide photocatalysts with wide band gaps, such as alkaline earth oxides, convert the energy of ultraviolet (UV) photons into electron-hole pairs. For nanoparticles of MgO, the energy needed to generate [...]

When metal oxides are grown from vapor onto a substrate, the exposed crystal face and the lattice mismatch of the substrate can influence the shape of the objects that form. [...]

The controlled synthesis of a variety of nanosized objects has been reported for several oxide materials. For tin oxide, there have been previous reports on the synthesis of nanoscale tubes, [...]

In the world of nanoparticles, nanoribbons are a newcomer to the variety of shapes that have been synthesized. Starting from molecular precursors, they have been fabricated from a variety of [...]

Porous silica, niobia, and titania with three-dimensional structures patterned over multiple length scales were prepared by combining micromolding, polystyrene sphere templating, and cooperative assembly of inorganic sol-gel species with amphiphilic triblock copolymers. The resulting materials show hierarchical ordering over several discrete and tunable length scales ranging from 10 nanometers to several micrometers. The respective ordered structures can be independently modified by choosing different mold patterns, latex spheres, and block copolymers. The examples presented demonstrate the compositional and structural diversities that are possible with this simple approach., Several approaches are currently available for the preparation of ordered structures at different length scales. For example, organic molecular templates can be used to form crystalline zeolite-type structures with ordering [...]