相关论文: Theoretical study of the pressure-induced structur…

Nitriding introduces nitrides into the surface of steels, significantly enhancing the surface me-chanical properties. By combining the variable composition evolutionary algorithm and first-principles calculations based on density functional…

Through machine learning force field accelerated structure search combined with first-principles calculations, we have studied the structures of new C-N compounds with different stoichiometric ratios, and found twelve new superhard C-N…

Using density functional theory calculations, many researchers have predicted that various tungsten-nitride compounds WN$_x$ ($x$ > 1) will be "ultra-compressible" or "superhard", $i.e.$ as hard as or harder than diamond. These compounds…

The pressure-induced transformation of diatomic nitrogen into non-molecular polymeric phases may produce potentially useful high-energy-density materials. We combine first-principles calculations with structure searching to predict a new…

We examine the effects produced by replacing B-B interlayer bonds by C-C bonds in AlMgB14-related boron network on its mechanical properties. The elastic constants, Vickers hardness and shear strength are evaluated by means of first…

Results of the first-principles calculations are presented for the group-VB metals V, Nb and Ta up to couple of megabar pressure. An unique structural phase transition sequence BCC-->(at 60 GPa) rhombohedral (angle=110.5 degree)-->(at ~ 160…

Nitrides, carbides and borides of transition metals are an attractive class of hard materials. Our recent preliminary explorations of the binary chemical compounds indicated that chromium-based materials are among the hardest transition…

Crystal structure searching and ab initio calculations have been used here to explore low-energy structures of boron carbides under high pressure. Under pressures of 85-110 GPa, a metastable B6C with R-3m symmetry is found to be…

Uranium nitrides have been the subject of intense research owing to their potential applications as advanced nuclear fuels. However, the phase diagram of the U-N system at low temperature and high pressure still remains unclear. In this…

Structural and mechanical properties of B12-based orthorhombic metal carboborides are studied on the basis of first principle DFT approach. The simulations predict the existence of a new family of phases of the composition MeC2B12 (Me=Mg,…

The discovery of monolayer MA$_2$Z$_4$ (M = transition metals; A = IVA elements; Z = VA elements, Science 369, 2020, 670-674) family has led another advance for facilitating and harnessing magnetism in low-dimensional materials. However,…

The synthesis of MgB2-based materials under high pressure gave the possibility to suppress the evaporation of magnesium and to obtain near theoretically dense nanograined structures with high superconducting, thermal conducting, and…

Using first principles calculation, the structural and mechanical properties of BP$_3$N$_6$ which adopts an orthorhombic structure with space group Pna2$_1$ (no. 33), were determined at three different pressure values (0, 20 and 42.4~GPa).…

First principle DFT simulations are employed to study structural and mechanical properties of orthorhombic B12-based metal carbide-borides. The simulations predict the existence of Ca- and Sr- based phases with the structure similar to that…

In this study, we analyzed the pressure-volume ($P-V$) relationship of elements using the equation of state at an ambient temperature within the multi-megabar pressure range of 200-300 GPa. We investigated the compressibility of elements…

Transition metal nitrides have been suggested to have both high hardness and good thermal stability with large potential application value, but so far stable superhard transition metal nitrides have not been synthesized. Here, with our…

The vibrational and structural properties of a hydrogen-rich Group IVa hydride, Ge(CH$_3$)$_4$, are studied by combining Raman spectroscopy and synchrotron X-ray diffraction measurements at room temperature and at pressures up to 30.2 GPa.…

We have performed ab initio calculations for new high-pressure phase of Ca-VI between 158-180 GPa. The study includes elastic parameters of mono- and poly-crystalline aggregates, electronic band structure, lattice dynamics and…

Owing to the fascinating physical characteristics of two-dimensional (2D) materials and their heterostructure, much effort has been devoted to exploring their basic physical properties as well as discovering other novel 2D materials.…

Under high pressure, the group-VB transition metals vanadium (V) and niobium (Nb) exhibit simple crystal structures but complex physical behaviors, such as anomalous compression-induced softening and heating-induced hardening (CISHIH).…