相关论文: Comparison of solid state crystallization of boron…
In this study, we report the synthesis and characterization of a novel tetragonal polymorph of Tb-doped Pb2P2O7. Single-crystal X-ray diffraction confirms the stabilization of the P41 and P43 enantiomorphs at room temperature due to the…
The crystal structure of CH3NH3PbBr3 perovskite has been investigated under high-pressure by synchrotron-based powder X-ray diffraction. We found that after the previously reported phase transitions in CH3NH3PbBr3 (Pm-3m->Im-3->Pmn21),…
Boron is a unique element, being the only element, all known polymorphs of which are superhard, and all of its crystal structures are distinct from any other element. The electron-deficient bonding in boron explains its remarkable…
Boron nitride (BN) is a material with outstanding technological promise because of its exceptional thermochemical stability, structural, electronic and thermal conductivity properties, and extreme hardness. Yet, the relative thermodynamic…
The existence of second-order structural phase transition in the SnS at a pressure of 16 GPa has been proved theoretically. The calculation is performed using the plane-wave pseudopotential approach to density-functional theory within 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…
SrRh2As2 exhibits structural phase transitions reminiscent to those of BaFe2As2, but crystallizes with three polymorphs derived from the tetragonal ThCr2Si2-type structure. The structure of \alpha-SrRh2As2 is monoclinic with a = 421.2(1)…
Quasi-hydrostatic compression of rhombohedral boron monosulfide (r-BS) has been studied up to 50 GPa at room temperature using diamond-anvil cells and angle-dispersive synchrotron X-ray diffraction. A fit of the experimental P-V data to the…
We report high pressure powder synchrotron x-ray diffraction studies on MFe2As2 (M=Ba, Ca) over a range of temperatures and pressures up to about 56 GPa using a membrane diamond anvil cell. A phase transition to a collapsed tetragonal phase…
Two-dimensional boron monolayer (borophene) stands out from the two-dimensional atomic layered materials due to its structural flexibility, tunable electronic and mechanical properties from a large number of allotropic materials. The…
Understanding the conditions which favor crystallisation or vitrification of liquids has been a long-standing scientific problem. Another connected, and not yet well understood question is the relationship between the glassy and the various…
Under a pressure of ~150 GPa solid molecular hydrogen undergoes a phase transition accompanied by a dramatic rise in infra-red absorption in the vibron frequency range. We use the Berry's phase approach to calculate the electric…
The assessed binary phase diagram of boron-carbon exhibits a single alloy phase designated "B4C" with rhombohedral symmetry occupying a broad composition range that falls just short of the nominal carbon content of 20%. As this composition…
In the present work we study the hadron-quark phase transition with boson condensation in asymmetric matter by investigating the binodal surface and extending it to finite temperature in order to mimic the QCD phase diagram. We consider a…
Twinning in crystalline materials plays an important role in many transformation and deformation processes, where underlying mechanisms can be strongly influenced by the structural, energetic and kinetic properties of associated twin…
The structural analogue of iron-based superconductors the BaMn$_2$P$_2$ and BaMn$_2$As$_2$ compounds under hydrostatic pressure upto 140 GPa were studied within the framework of DFT+U. The transition from an antiferromagnetic (AFM)…
Polymer blends offer an exciting material for various potential applications due to their tunable properties by varying constituting components and their relative composition. Our simulation results unravel an intrinsic relationship between…
We have studied single crystals of $C_{70}$ by Raman scattering and photoluminescence in the pressure range from 0 to 31.1 GPa. The Raman spectrum at 31.1 GPa shows only a broad band similar to that of the amorphous carbon without any trace…
Density functional perturbation theory calculations of alpha-quartz using extended norm conserving pseudopotentials have been used to study the elastic properties and phonon dispersion relations along various high symmetry directions as a…
We identify a new family of boron-rich compounds consisting of interconnected B$_{12}$ icosahedra, and electropositive guest atoms ($X$) in interstitial sites. These structures were found through first-principles crystal structure…