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31NMR spectra of several inorganic phosphates have been examined both in the crystalline and the glassy states. The parameter (Zeff/r)q clearly demarcates ortho-, pyro- and meta-phosphates in terms of the 31P chemical shifts. Based on such a diagram, inorganic phosphate glasses are found to consist essentially of metaphosphate units. NMR resonance of the glasses are generally much broader than those of crystalline phosphates.

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A simple route involving urea as the nitrogen source has been employed to carry out boron nitride coating on carbon fibers, multi-walled carbon nanotubes and inorganic nanowires. The process involves heating the carbon fibers and nanotubes or inorganic nanowires in a mixture of H3BO3 and urea, followed by a heat treatment at 1000°C in a N2 atmosphere. We have been able to characterize the BN coating by transmission electron microscopy as well as X-ray photoelectron spectroscopy. The urea decomposition route affords a simple method to coat boron nitride on one-dimensional nanostructures.

The liquid and the glassy phases of 2,2-dimethylbutane have been investigated by isothermal isobaric ensemble Monte Carlo simulation. Thermodynamic Properties and radial distribution functions for both the liquid and the glass have been obtained. The radial distribution functions have been classified into three types based on the accessibility of the group. It has been shown that the structure of the Iiquid and the glass can be understood in terms of the above classification of the radial distribution functions. Molecular reorientation plays an important role in the structural rearrangement accompanying glass formation. As much as 35% of the contribution to the increase in the intermolecular interaction energy on vitrification is due to the reorientation of the neighbouring pairs of molecules. The observed changes in the dimerisation energy and the bonding energy distribution function are consistent with the observed structural changes.

C60Br8, unlike C60Br6 and C60Cl6, forms a solid charge-transfer compound with tetrathiafulvalene (TTF), the composition being C60Br8 (TTF)8.The unique complex-forming property of C60Br8 can be understood on the basis of the electronic structures of the halogenated derivatives of C60. Molecular orbital calculations show that the low LUMO energy of C60Br8 compared with the other halogen derivatives renders the formation of the complex with TTF favourable, the four virtual LUMOs being able to accept 8 electrons. The Raman spectrum of C60Br8(TTF)8 shows a marked softening of the bands (-46 cm-1 on average) with respect to C60Br8, suggesting that indeed 8 electrons are transferred per C60Br8 molecule,one from each TTF molecule.The complex is weakly paramagnetic and shows a magnetic transition around 80 K.

Photosynthesis that occurs in plants involves both the oxidation of water and the reduction of carbon dioxide. Plants carry out these reactions with ease, by involving electron‐transport chains. In this article, hydrogen generation by the reduction of water in the laboratory by using semiconductor nanostructures through artificial photosynthesis is examined. Dye‐sensitized photochemical generation of hydrogen from water is also discussed. Hydrogen generation by these means has great technological relevance, since it is an environmentally friendly fuel. The way in which oxygen can be generated by the oxidation of water using metal oxide catalysts is also shown.

All superconductors are solids in their superconducting state, this canonical electronic state of matter presently having only been observed well below the melting temperature of the solid. The discovery of high‐temperature superconductivity in cuprates has widened significantly our horizons of the theoretical understanding of the physical phenomenon. A number of observations point to the possibility that superconductors with a high superconducting transition temperature may not be conventional Bardeen–Cooper–Schrieffer (BCS) superconductors, but rather derive from the Bose–Einstein condensation of real‐space pairs. While BCS superconductors exist in the solid state (probably with the exception of metallic liquid hydrogen at ultrahigh pressures), we argue here that a superconducting charged Bose liquid may be found in a true liquid state of condensed matter at ambient pressure. An experimental scenario is outlined in fluid metal–ammonia solutions for stabilizing and observing a high‐temperature superconducting liquid (ca. 230 K) or at least a vitreous superconductor in the corresponding quenched solutions (ca. 160 K).

Trisulfide molybdenum complexes have been employed to produce nanotubes by simple heating in a stream of hydrogen. Bamboo-like stacking (see Figure) was observed, suggesting that the stimulus for the growth of MoS2 nanotubes is similar to that of their carbon equivalents. The wide experience gained with trisulfide complexes directs this technique towards the preparation of other layered sulfide nanotubes, although other precursors are also shown to be successful.

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTExtended x-ray absorption fine structure studies of bimetallic copper-nickel/.gamma.-alumina catalystsG. Sankar, S. Vasudevan, and C. N. R. RaoCite this: J. Phys. Chem. 1986, 90, 21, 5325–5328Publication Date (Print):October 1, 1986Publication History Published online1 May 2002Published inissue 1 October 1986https://pubs.acs.org/doi/10.1021/j100412a084https://doi.org/10.1021/j100412a084research-articleACS PublicationsRequest reuse permissionsArticle Views74Altmetric-Citations6LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InRedditEmail Other access options Get e-Alerts

Assemblies of covalently linked single-walled carbon nanotubes with superior gas adsorption properties have been prepared and characterized.

Substitution of Ca by Y in TlCaBa 2 Cu 2 O y does not favour superconductivity, but substitution of Tl by Pb or of Ca by Ln (Ln = Y or rare earth) in TlCaSr 2 Cu 2 O y results in high T c superconductivity (T c π 60-90 K). TlCa 1-x Ln x Sr 2 Cu 2 O y is a new series of high T c superconductors, but the x = 0.0 composition does not exhibit bulk superconductivity.