Publications

Abhängigkeit der Reaktivität von Ag‐ und Ni‐Clustern auf festen Trägern von der Clustergröße

Reaktiver als Silber‐und Nickelmetall sind Kleine Cluster aus diesen Elementen, wie Reaktivitätsstudien mit O 2 sowie H 2 S und CO zeigen. So ist zum Beispiel die Spaltung von O 2 an kleinen Ag‐Clustern bevorzugt, und der Anteil der O 2 ‐Moleküle, die gespalten werden, hängt nicht, wie bei größeren Clustern und Silbermetall, von der Temperatur ab. Die Änderung der Reaktivität ist dann am größten, wenn der Übergang vom Metall zum Isol tor vollzogen wird‐ein für die heterogene Katalyse wichtiger Befund.

Electroluminescence from GaN-polymer heterojunction (vol 131, pg 2612, 2011)

II. Transition Metal Oxides (including Cuprate Superconductors)

No abstract is provided for this article.

Adsorption of carbonyl compounds on clean and modified Cu(110) surfaces: A combined eels-ups study

HCHO, CH3CHO and (CH3)2CO are shown to adsorb molecularly on a clean Cu(110) surface at 80 K and transform to different surface species on increasing the temperature. On a Cu(110) surface modified with aluminum, adsorption of HCHO, CH3CHO and (CH3)2CO is dissociative. The two aldehydes undergo chemical transformations on a Cu(110) surface covered with atomic oxygen.

Composition dependence of giant magnetoresistance in La1−CaMnO3 (0.1 ≤ x ≤ 0.9)

We have studied the resistivity (ϱ) and the magnetoresistance (MR) in sintered samples of La 1−x Ca x MnO 3 for 0.1 ≤ x ≤ 0.9 in the temperature range 4.2K ≤ T ≤ 400K in magnetic fields H ≤ 6T. We have observed giant negative magnetoresistance in the whole composition range, although the magnitude of MR depends on the level of doping, the peak in the magnitude of MR [ (ϱ(H) − ϱ(0)) ϱ(0) ] at 6T being be as high as 90%. The magnitude of the MR generally increases as the temperature corresponding to the MR peak decreases. All the samples with x ≤ 0.5 show a ferromagnetic transition with the temperature dependence of ϱ showing a metallic behavior ( dϱ dT > 0) below the Curie temperature. The sample with x = 0.9 shows insulating behavior over the entire temperature range but the MR shows a peak at low temperatures.

Reaction with organic halides as a general method for the covalent functionalization of nanosheets of 2D chalcogenides and related materials

No abstract is provided for this article.

A magnetic susceptibility study of spin-state transitions in rare-earth trioxocobaltates(III)

Rare-earth trioxocobaltates(III), Ln[CoO3], with Ln = Pr, Nd, Tb, Dy, and Yb exhibit low-spin to high-spin transitions of cobalt characterised by a maximum in the Δχ–1 against temperature plots where Δχ is the cobalt contribution to the magnetic susceptibility. The susceptibility behaviour is distinct from that of La[CoO3] which shows a plateau in the χ–1–T curve accompanied by a structural transition. The temperature at which the Δχ–1–T curve shows a maximum increases with the decrease in the size of the rare-earth ion. The susceptibility behaviour of solid solutions of La1 –xNdxCoO3 has been investigated to see how the behaviour characteristic of Nd[CoO3] changes to that of La[CoO3].

ChemInform Abstract: Structural Aspects of High‐Temperature Cuprate Superconductors

Review: (55 refs.

The two faces of chemistry in the developing world

No abstract is provided for this article.

Iron, cobalt and nickel nanoparticles encapsulated in carbon obtained by the arc evaporation of graphite with the metals

Arc evaporation of graphite with Fe, Co and Ni yields two distinct types of metal nanoparticles, wrapped in graphitic layers and highly resistant to oxidation. Electron microscopy shows that the metal particles (10–40 nm) in the stub region are encap- sulated in carbon onions, the particles in the soot being considerably smaller (2–15 nm). The metal particles in the soot are either ferromagnetic with lowered Curie temperatures or superparamagnetic.

Monte Carlo simulation of isopentane glass

Monte Carlo calculations on liquid and glassy isopentane have been performed by using transferable intermolecular potential functions (t. i. ps). Thermodynamic properties, radial distribution functions, coordination number distributions, etc., calculated for the liquid are in reasonable agreement with the experimental values. By quenching the liquid, we have obtained the glass-transition temperature from the temperature variation of intermolecular energy, volume and the heat of vaporization. Radial distribution functions suggest a structure of the glass primarily influenced by geometrical factors and with no preference for any particular orientation ; the peak around 4.0 Å (1 Å = 10 -10 m = 10 -1 nm) between the more exposed carbon atoms seems to be the characteristic of densely packed hydrocarbons. The histogram of the nearest-neighbour distribution shows a shift towards higher coordination in the glassy state. Interesting differences are found between the liquid and the glass in the dimerization energy and bonding energy distribution functions. Narrower distribution is found on vitrification in the dihedral angle distribution function for rotation around the central C–C bond.

Electronic structures of H2O⋅BF3 and related <i>n</i>–<i>v</i> addition compounds: A combined EELS–UPS study in vapor phase

The detailed electronic structure of the n–v addition compound H2O⋅BF3 has been investigated for the first time by a combined use of electron energy loss spectroscopy (EELS) and UV photoelectron spectroscopy (UPS) augmented by MO calculations. The calculated molecular orbital energies of H2O⋅BF3 agree well with the UPS results and have been used to assign the electronic transitions obtained from EELS and to construct an orbital correlation diagram.

Nanowires, nanobelts and related nanostructures of <font>Ga</font>₂<font>O</font>₃

No abstract is provided for this article.

Physical chemistry of high-temperature oxide superconductors [Erratum to document cited in CA110(24):223296s]

ADVERTISEMENT RETURN TO ISSUEPREVArticlePhysical chemistry of high-temperature oxide superconductors [Erratum to document cited in CA110(24):223296s]T. V. Ramakrishnan and C. N. R. RaoCite this: J. Phys. Chem. 1989, 93, 26, 8388Publication Date (Print):December 1, 1989Publication History Published online1 May 2002Published inissue 1 December 1989https://pubs.acs.org/doi/10.1021/j100363a028https://doi.org/10.1021/j100363a028research-articleACS PublicationsRequest reuse permissionsArticle Views32Altmetric-Citations-LEARN 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

Electronic structures of solids by electron-energy-loss spectroscopy carried out using and electron microscope: oxygen-K and metal-L edges of transition metal oxides

Electron-energy-loss spectra, recorded from ultramicro quantities (<10–12 g), reveal L2,3 edges the energy and intensity of which vary systematically with oxidation state in a series of transition metal oxides; the first ever evidence for structure-sensitive features in oxygen K-edges is reported.

CCDC 267378: Experimental Crystal Structure Determination

An entry from the Cambridge Structural Database, the world’s repository for small molecule crystal structures. The entry contains experimental data from a crystal diffraction study. The deposited dataset for this entry is freely available from the CCDC and typically includes 3D coordinates, cell parameters, space group, experimental conditions and quality measures.

Use of the liquid–liquid interface for generating ultrathin nanocrystalline films of metals, chalcogenides, and oxides

The air–water interface has traditionally been employed to prepare particle assemblies and films of metals and semiconductors. The interface between water and an organic liquid, however, has not been investigated sufficiently for possible use in preparing nanocrystals and thin films of materials. In this article, we demonstrate the use of the liquid–liquid interface as a medium for preparing ultrathin films of metals, chalcogenides and oxides. The method involves the reaction at the interface between a metal-organic compound in the organic layer and an appropriate reagent for reduction, sulfidation, etc. in the aqueous layer. Some of the materials discussed are nanocrystalline films of gold, CuS, CuSe, CuO, and Cu(OH)2 formed at the liquid–liquid interface. The results reported in this article should demonstrate the versatility and potential of the liquid–liquid interface for preparing nanomaterials and ultrathin films and encourage further research in this area.

Metal-insulator transitions in metal clusters: a high-energy spectroscopy study of palladium and silver clusters

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTMetal-insulator transitions in metal clusters: a high-energy spectroscopy study of palladium and silver clustersV. Vijayakrishnan, A. Chainani, D. D. Sarma, and C. N. R. RaoCite this: J. Phys. Chem. 1992, 96, 22, 8679–8682Publication Date (Print):October 1, 1992Publication History Published online1 May 2002Published inissue 1 October 1992https://doi.org/10.1021/j100201a002Request reuse permissionsArticle Views402Altmetric-Citations90LEARN 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 InReddit PDF (460 KB) Get e-Alerts