相关论文: Crystal structure of dense pseudo-cubic boron allo…

Two novel three-dimensional (3D) crystal structures of carbon (C) and germanium carbide (GeC2) were predicted using first-principles density-functional theory (DFT) calculations. These newly discovered 3D carbon allotrope and GeC2 are in…

Boron carbide thin films were synthesised by laser-assisted chemical vapour deposition (LCVD), using a CO2 laser beam and boron trichloride and methane as precursors. Boron and carbon contents were measured by electron probe microanalysis…

We applied synchrotron single-crystal X-ray diffraction in a diamond anvil cell at 48-51 GPa and first-principles theoretical calculations to study the crystal structure of solid atomic iodine at high pressure. We report the synthesis of…

The structure of dielectric perovskite BaZrO$_3$, long known to be cubic at room temperature without any structural phase transition with variation of temperature, has been recently disputed to have different ground state structures with…

Large-area single-crystal surface structures were successfully prepared on Cu(111) substrate with boron deposition, which is critical for prospective applications. However, the proposed borophene structures do not match the scanning…

We present here the results of structural studies on multiferroic (1-x)Bi(Ni1/2Ti1/2)O3-xPbTiO3 solid solution using Rietveld analysis on powder x-ray diffraction data in the composition range 0.35 to 0.55. We have determined precisely the…

Original carbon allotropes, orthorhombic C8, C10, C12 and C14 presenting mixed sp2 and sp3 carbon hybridizations exhibiting ethene like and propadiene like embedded units are proposed from crystal chemistry and calculations within the…

The phase relations in boron have been investigated at high pressure and high temperature using a multianvil apparatus, and the quenched sample has been analyzed by x-ray diffraction, Raman spectra and transmission electron microscopy. We…

A first cobalt boride with the Co:B ratio below 1:1, Co5B16, was synthesized under high-pressure high-temperature conditions. It has a unique orthorhombic structure (space group Pmma, a = 19.1736(12), b = 2.9329(1), and c = 5.4886(2) {\AA},…

In this paper we propose a new pseudo-phase crystal structure, based on an orthorhombic distortion of the diamond structure, for the ground-state $\alpha$-phase of plutonium. Electronic-structure calculations in the generalized-gradient…

The structure and physical properties of the Zr-stabilized, nonstoichiometric molybdenum diboride superconductor are reported. Good quality material of the diboride structure type can only be obtained by partial substitution of Zr for Mo,…

Results of X-ray diffraction experiments on solid oxygen at low temperature and at pressures up to 10 GPa are presented.A careful sample preparation and annealing around 240 K allowed to obtain very good diffraction patterns in the…

Pressure-induced transitions from ordered intermetallic phases to substitutional alloys to semi-ordered phases were studied in a series of bismuth tellurides. Using angle-dispersive x-ray diffraction, the compounds Bi4Te5, BiTe, and Bi2Te…

We report on the structural phase transitions in the S doped FeSe superconductor by powder synchrotron X ray diffraction at high pressures up to 18.5 GPa under compression and decompression modes. In order to create high quasi hydrostatic…

Boron nitride (BN) is an exceptional material and among its polymorphs, two-dimensional (2D) hexagonal and three-dimensional (3D) cubic BN (h-BN and c-BN) phases are most common. The phase stability regimes of these BN phases are still…

New ultra-hard rhombohedral B2N2 and BC2N - or hexagonal B6N6 and B3C6N3 - are derived from 3R graphite based on crystal chemistry rationale schematizing a mechanism for 2D => 3D transformation. Full unconstrained geometry optimizations…

We present a combined X-ray and neutron diffraction, Raman spectroscopy, and 121Sb NMR studies of AgSbTe2, supported by first-principles calculations aiming to elucidate its crystal structure. While diffraction methods cannot unambiguously…

Novel ordered intermetallic compounds have stimulated much interest. Ru-Al alloys are a prominent class of high-temperature structural materials, but the experimentally reported crystal structure of the intermetallic Ru2Al5 phase remains…

Through a systematic structural search we found an allotrope of carbon with Cmmm symmetry which we predict to be more stable than graphite for pressures above 10 GPa. This material, which we refer to as Z-carbon, is formed by pure sp3 bonds…

Boron nitride structures have excellent thermal and chemical stabilities. Based on state-of-art theoretical calculations, we propose a wide gap semiconducting BN crystal with a three-dimensional hyperhoneycomb structure (Hp-BN), which is…