The structure of molten LaBr3 was investigated by X-ray diffraction and molecular dynamics simulations. It was found that the short range structure of molten LaBr3 is very similar to that of molten LaCl3, except for some structural features such as interionic distances based on the difference of anion sizes. In the MD simulation, the shear viscosity of molten LaBr3 was estimated from the struct...

Fully relativistic four-component self-consistent field and correlated calculations at the Mo”ller– Plesset second-order perturbation theory level ~MP2! have been performed for the monofluorides and monoand trihydrides of lanthanum, lutetium, actinium, and lawrencium. The calculated spectroscopic constants are in good agreement with available experimental data. The calculated bond lengths have ...

We study from first principles two lanthanum silicate nitride compounds, LaSi3N5 and La3Si6N11, pristine as well as doped with Ce ion, in view of explaining their different emission color, and characterising the luminescent center. The electronic structures of the two undoped hosts are similar, and do not give a hint to quantitatively describe such difference. The 4f → 5d neutral excitation of ...

The local structure of apatite-type lanthanum silicates of general formula La9.33+x(SiO4)6O2+3x/2 has been investigated by combining the atomic pair distribution function (PDF) method, conventional X-ray and neutron powder diffraction (NPD) data and density functional theory (DFT) calculations. DFT was used to build structure models with stable positions of excess oxide ions within the conducti...

Data deposited in the Cambridge Structural Database (CSD) for compounds of scandium, yttrium, lanthanum and lutetium(III) have been analysed to assess structural similarities complexes different metal ions. 29 sets Sc, Y, La Lu where at least three elements form with same ligands identified their crystal structures analysed. In 14 them, scandium lutetium coordination number; remaining 15 they d...

Over 30 years of surface science research on metal hexaborides are reviewed. Of this class of compounds, lanthanum hexaboride has been the subject of the majority of the studies because of its outstanding properties as a thermionic emitter. The use of LaB6 cathodes as an electron source stems from the unusually low work function of ∼2.5 eV for the (100) surface combined with a low evaporation r...

The new lanthanum vanadium oxyselenides LaVSe2O, La5V3Se6O7, La5V3Se7O5, La7VSe5O7, and La13V7Se16O15 were synthesized in eutectic NaI/KI fluxes, and their crystal structures were determined using single-crystal and powder X-ray diffraction experiments. LaVSe2O and La5V3Se6O7 adopt known structure types, whereas La5V3Se7O5, La7VSe5O7, and La13V7Se16O15 crystallize in hitherto unknown structure ...

Besides the ‘‘intrinsic’’ colossal magnetoresistance effect observed in single crystals, the polycrystalline manganate compounds also exhibit an ‘‘extrinsic’’ magnetoresistance related to the presence of grain boundaries. We report electrical transport and magnetic measurements carried out on a bigrain sample extracted from a floating zone method-grown rod of calcium doped lanthanum manganate. ...