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The electronic structure of the inter-metallic compounds LaMg, YCu, YMg, and YRh which crystallize in the CsCl-type structure (B2) are studied by means of the self-consistent tight binding-linear muffin tin orbital method. The total energies are computed as a function of volume and fitted to the Birch equation of state. The ground state properties of these compounds such as the equilibrium lattice parameter; the bulk modulus and the cohesive properties are calculated and compared with the available experimental results. We find a good agreement between the theory and experiment. The partial number of electrons at different sites and the total density of states (DOS) are calculated as a function of volume. We observed a continuous transfer of electrons from site ‘B’ to site ‘A’ as a function of volume. In addition, the electronic structure and the DOS histogram of these compounds are computed and plotted. They are compared with the available literature. [Copyright &y& Elsevier]

The article presents a study on marine organisms as a source of metabolites. Several classes of metabolites and sterols are believed to be produced by soft corals and other marine organisms. It notes that the lack of sterol biosynthesis in human are known to cause disorders such as the Smith-Lemli-Opitz syndrome. The study found out that there are 561 new polar steroids from 16 species of octocoral families which can help chemists in looking for enzymes suitable for targeted biological activity.

Zinc doped cobalt ferrite spinel nanoparticles were prepared by the microwave combustion method. All the samples were characterized by using X-ray diffraction technique (XRD), Scanning Electron Microscopy, energy dispersive X-ray analysis, UV–visible diffuse reflectance spectroscopy, Fourier transformed infrared (FT-IR) spectroscopy and vibrating sample magnetometry. The XRD patterns confirmed the formation of single phase CoFe 2 O 4 inverse spinel structure without impurities. The lattice parameter increased from 8.380 to 8.396 Å with increasing Zn 2+ fraction. The average crystallite sizes obtained by a Scherrer method varied between 46.22 nm and 30.79 nm. The estimated band gap energy values increases with an increasing zinc fraction (1.88–2.10 eV). The elemental composition of Zn, Co, and Fe was qualitatively obtained from energy dispersive X-ray (EDX) analysis. [ABSTRACT FROM AUTHOR]