In this paper, we report our theoretical prediction of a boron-rich binary compound, YB6, with Pm3m space group subjected to pressures from 0 to 50 GPa. Calculations of first principles are performed to investigate the elastic, vibrational and electronic structural properties using the Density Functional Theory (DFT) within the plane-wave pseudopotential method based on the generalized gradient approximation (GGA) proposed by Perdew-Wang (PW91). We discuss the structural stability based on elastic constants analysis (C ij ) obtained with static finite strain technique. Bulk (BH), Shear (GH) and Young's modulus (EH) as well as Poisson's ratio (ν), were calculated with the Voigt-Reuss approximation derived from ideal polycrystalline aggregate. Other parameters such as Vickers Hardness (Hv), Pugh's ratio GH/BH, the speed of sound (vm) and Debye temperature (θD) were given by elastic modules. We found that C 11 and C 12 elastic constants and elastic modulus monotonically increase while C 44 decrease as a function of pressure; consequently, the structure is dynamically stable and ductile besides that hardness decreases under pressure. The phonon dispersion curves showed no imaginary phonon frequency in the entire Brillouin Zone (BZ) under pressure, showing stable Pm3m space group. Finally, the density of states (DOS) at the Fermi level decreases with increasing pressure, due to the decrease of the contribution of B 2-p states.

Polar magnets are promising materials for new applications as multiferroics or in spintronics. In double corundum-related oxides, the cation ordering imposes a polar structure and the use of high pressure facilitates the insertion of magnetic cations into the compounds. Here we present the high-pressure synthesis of a new polar and ferrimagnetic corundum derivative Mn 2 InSbO 6 , which adopts the ordered-ilmenite-type structure. Neutron powder diffraction reveals that the high-temperature nearly collinear ferrimagnetic phase evolves to an incommensurate helical structure with k δ = [0 0 k z ] propagation vector, which then locks to the commensurate value of k z = 1/8. This complex magnetic behavior is likely to be related to magnetic frustration and the polar nature of the ordered double corundum structure.

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Herein we report the Peierls-like transition in the high-pressure ilmenite-type MnVO3. The first-order structural transition from a low-temperature P-1 to a high-temperature R-3 occurs at 475 K, accompanied by a...

The crystal structure and magnetic properties of Nb1−xYxB2.5 with 0.000 ≤ x ≤ 0.050 compositions are reported. Rietveld refinement of XRD patterns shows that the partial substitution with yttrium atoms in niobium sites increases the unit cell volume. Magnetization measurements show that the critical temperature (T c ) changes from 9.0 K to 9.9 K for x = 0.000 and x = 0.050, respectively. Using the XPS measurements, the Nb 3d and B 1s core levels were identified, and the XPS valence band of XPS was measured. Our results show an increase in the valence band at zero eV as the yttrium content increases, which might be related to the T c change. The electron-phonon coupling constant was calculated from the McMillan equation; our results indicate that the Nb1−xYxB2.5 compounds are weak-coupled superconductors. Our work stablishes the effect of light doping on the structure and physical properties of these superconductors.