Related papers: Cotunnite-structured titanium dioxide: the hardest…
In this work, sintered polycrystalline cubic boron nitride (cBN) compacts, with titanium carbonitride (TiC0.7N0.3) and titanium nitride (TiN), respectively, as binders, were prepared at temperature of 1450{\deg}C and pressure of 5.5 GPa…
The molecular structures of amorphous silica and crystalline quartz are used to predict their intrinsic strength and fracture toughness together with the theoretical strength of silicon dioxide. At the atomic scale, the amorphous silica is…
A novel oxychloride, Sr$_{3}$Ni$_{2}$O$_{5}$Cl$_{2}$, was synthesized for the first time under high pressure of 10 GPa at 1400 ${}^\circ$C, motivated by a theoretical prediction of its potential superconductivity under ambient pressure.…
A number of successful theoretical models of hardness have been developed recently. A thermodynamic model of hardness, which supposes the intrinsic character of correlation between hardness and thermodynamic properties of solids, allows one…
The MgB2 - based material high-pressure synthesized at 2 GPa and 800 C for 1 h from Mg and B (taken in the stoichiometry ratio of MgB2) with addition of 2-10 wt% of Ti demonstrated the critical current density (jc) higher than 100 kA/cm^2…
A brief overview on high-pressure synthesis of superhard and ultrahard materials is presented in this tutorial paper. Modern high-pressure chemistry represents a vast exciting area of research which can lead to new industrially important…
A recent experimental study reported the successful synthesis of an orthorhombic FeB4 with a high hardness of 62 GPa, which has reignited extensive interests on whether transition metal borides (TRBs) compounds will become superhard…
The Cassini-Huygens mission detected large negative ions in Titan's ionosphere at pressures as low as $10^{-6}$ torr. These ions ultimately polymerize to form Titan's complex organic haze particles, which are observed throughout the…
The structural properties of Thallium (III) oxide (Tl2O3) have been studied both experimentally and theoretically under compression at room temperature. X-ray powder diffraction measurements up to 37.7 GPa have been complemented with ab…
Using finite-temperature phonon calculations and machine-learning methods, we calculate the mechanical stability of about 400 semiconducting oxides and fluorides with cubic perovskite structures at 0 K, 300 K and 1000 K. We find 92…
The measurement of superconductivity at above 200K in compressed samples of hydrogen sulfide and lanthanum hydride at 250K is reinvigorating the search for conventional high temperature superconductors. At the same time it exposes a…
Recent advances in theoretical structure prediction methods and high-throughput computational techniques are revolutionizing experimental discovery of the thermodynamically stable inorganic materials. Metastable materials represent a new…
We have discovered a new iron pnictide oxide superconductor (Fe2As2)(Sr4(Mg,Ti)2O6). This material is isostructual with (Fe2As2)(Sr4M2O6) (M = Sc, Cr, V), which were found in previous studies. The structure of this compound is tetragonal…
Recent discovery of superconductive rare earth/actinide superhydrides has ushered in a new era of superconductivity research at high pressures. This distinct type of clathrate metal hydrides was first proposed for alkaline-earth-metal…
Silicon carbide is a hard, semiconducting material presenting many polytypes, whose behavior under extreme conditions of pressure and temperature has attracted large interest. Here we study the mechanical properties of 3C-SiC over a wide…
We introduce a computational approach to estimate the hardness and stiffness of diamond surfaces and nanoparticles by studying their elastic response to atomic nanoindentation. Results of our ab initio density functional calculations…
Several fcc- and hcp-structured Ir-Os alloys have been recently studied up to 30 GPa at room temperature by means of synchrotron-based X-ray powder diffraction in diamond anvil cells. Using their bulk moduli -which increase with increasing…
Microstructure and mechanical properties of bulk polycristalline boron phosphides (cubic BP and rhombohedral B12P2) have been studied by scanning electron microscopy and micro- and nanoindentation. The obtained data on hardness, elastic…
The search of new superhard materials has received a strong impulse by industrial demands for low-cost alternatives to diamond and $c$-BN, such as metal borides. In this Letter we introduce a new family of superhard materials, "fused…
Noting the structural relationships between phases of carbon and boron carbide with phases of boron nitride and boron subnitride, we investigate their mutual solubilities using a combination of first principles total energies supplemented…