Nickel cobaltite, NiCo2O4, has been synthesized by sol–gel and thermal decomposition techniques and the surface composition studied with Auger (AES) and X-ray photoelectron spectroscopies (XPS). The asintroduced samples are near-stoichiometric, although samples fabricated by thermal decomposition tend to be oxygen-defi cient by approximately 25% of the predicted spinel concentration. Nickel 2p ...

Transition metal ions doped NaCaAlPO4F3 phosphors have been synthesized using a solid state reaction method. The prepared samples are characterized by powder XRD, SEM, optical absorption, EPR, PL and FT-IR techniques. The XRD studies confirm the crystal structure of prepared phosphor samples as monoclinic system. SEM images show nanoclusters. Optical absorption and EPR spectra of TM ions doped ...

Octahedral, trigonal prismatic, and capped square pyramidal structures have been optimized for the Ru(6)C(CO)(n) clusters (15 ≤ n ≤ 20) using density functional theory. The experimentally known very stable Ru(6)C(CO)(17) is predicted to have an octahedral structure in accord with experiment as well as the Wade-Mingos rules. The stability of Ru(6)C(CO)(17) is indicated by its high carbonyl disso...

The structures of many important functional oxides contain networks of metal-oxygen polyhedral units i.e. MOn. The correlation between the configurations and connectivities of these MOn to properties is essentially important to be well established to conduct the design, synthesis and application of new MOn-based functional materials. In this paper, we report on an atomic-scale solution-chemistr...

This work describes the first hydrothermal synthesis in fluoride medium of Ni-Al montmorillonite-like phyllosilicates, in which the only metallic elements in the octahedral sheet are Ni and Al. X-ray diffraction, chemical analysis, thermogravimetric and differential thermal analysis, scanning electron microscopy and transmission electron microscopy confirm that the synthesized samples are montm...

Within the framework of density functional theory using the projector augmented-wave (PAW) method, we present some energetic properties of atomic oxygen interstitials in crystalline Ni, i.e. the insertion and activation energies of the O diffusion. Concerning the activation energy, two pathways for the migration process are studied. The charge transfer process between atomic oxygen and nickel a...

The electronic spin and valence states of iron in lower-mantle silicate perovskite have been previously investigated at high pressures using various experimental and theoretical techniques. However, experimental results and their interpretation remain highly debated. Here we have studied a wellcharacterized silicate perovskite starting sample [(Mg0.9,Fe0.1)SiO3] in a chemically inert Ne pressur...

We have solved the single crystal structure to 1.2-A resolution of the Z-DNA sequence d(CGCGCG) soaked with copper(II) chloride. This structure allows us to elucidate the structural properties of copper in a model that mimics a physiologically relevant environment. A copper(II) cation was observed to form a covalent coordinate bond to N-7 of each guanine base along the hexamer duplex. The occur...

Particles of sub-micron size possess significant capacity to adsorb organic molecules from aqueous media. Semiconductor photocatalysts in particle form could potentially be utilized for dye removal through either physical adsorption or photo-induced chemical process. The photocatalytic and adsorption capabilities of Cu₂O particles with various exposed crystal facets have been studied through se...

The brom oarsenates(lll) [Et4N]3[A s3B rl2] (1). [Ph4P]2[A s2Brs] (2), [(/z-prop)4N]2[A s2Brs] (3) and {[pipH]3[A s2Bn,] • [pipH]Br} (4) have been prepared and their structures established by X-ray structural analysis. The central As atom in the novel face-bridged trioctahedral species [A s;Br,2] displays an effectively regular octahedral coordination in one of the two independent anions in the...