Related papers: High Energy Density Mixed Polymeric Phase From Car…
Understanding the high-pressure behavior of C-H system is of great importance due to its key role in organic, bio-, petroleum and planetary chemistry. We have performed a systematic investigation of the pressure-composition phase diagram of…
We have studied by means of high-pressure x-ray diffraction the structural stability of Ni2Mo3N, Co3Mo3N, and Fe3Mo3N. We also report ab initio computing modeling of the high-pressure properties of these compounds, Pd2Mo3N, and Pt2Mo3N. We…
First-principles molecular dynamics (FPMD) simulations are performed on 6 and 12% Na in dense liquid N. A detailed description of structural and electronic properties leading to an understanding of the effect of Na-doping on the…
The influence of the oxygen segregation into Mg-B-O inclusions (which are oxygen enriched as compared to the matrix material) and the formation of boron enriched phases (with near MgB12 composition) in MgB2 structure on pinning in magnesium…
The search and exploration of new materials not found in nature is one of modern trends in pure and applied chemistry. In the present work, we report on experimental and \textit{ab initio} density-functional study of the…
The phase transition from hadronic matter to quark matter at high density might be a strong first order phase transition in presence of a large surface tension between the two phases. While this implies a constant-pressure mixed phase for…
Carbon exhibits both a layered ground state structure that produces two-dimensional (2D) nanosheets and a non-layered diamond structure created under high pressure conditions. Motivated by this metastability relationship, we revisit the…
We use ab initio density functional calculations to study the formation and structural as well as thermal stability of cellular foam-like carbon nanostructures. These systems with a mixed $sp^2/sp^3$ bonding character may be viewed as…
A novel allotrope of carbon with $P2/m$ symmetry was identified during an \emph{ab-initio} minima-hopping structural search which we call $M10$-carbon. This structure is predicted to be more stable than graphite at pressures above 14.4 GPa…
We have investigated the pressure-induced phase transition and superconducting properties of niobium disulfide (NbS$_2$) based on the density functional theory. The structures of NbS$_2$ at pressures from 0 to 200 GPa were predicted using…
Understanding high-pressure transitions in prototypical linear diatomic molecules, such as hydrogen, nitrogen, and oxygen, is an important objective in high-pressure physics. Recent ultrahigh-pressure study on hydrogen revealed that there…
The paper establishes exact lower bound on the effective elastic energy of two-dimensional, three-material composite subjected to the homogeneous, anisotropic stress. It is assumed that the materials are mixed with given volume fractions…
Molybdenum carbide (Mo2C) nanoparticles and thin films are particularly suitable catalysts for catalytic fast pyrolysis (CFP) as they are effective for deoxygenation and can catalyze certain reactions that typically occur on noble metals.…
Cooperative adsorption of gases by porous frameworks permits more efficient uptake and removal than does the more usual non-cooperative (Langmuir-type) adsorption. Cooperativity, signaled by a step-like isotherm, is usually attributed to a…
Gas hydrates are systems of prime importance. In particular, hydrogen hydrates are potential materials of icy satellites and comets, and may be used for hydrogen storage. We explore the H2O-H2 system at pressures in the range 0-100 GPa with…
A thorough in situ characterization of materials at extreme conditions is challenging, and computational tools such as crystal structural search methods in combination with ab initio calculations are widely used to guide experiments by…
Ground state structures found in nature are in many cases of high symmetry. But structure prediction methods typically render only a small fraction of high symmetry structures. Especially for large crystalline unit cells there are many low…
We investigated the stability of polymeric CO2 over a wide range of pressures, temperatures, and chemical environments. We find that the I-42d polymeric structure, consisting of a three-dimensional network of corner sharing CO4 tetrahedra,…
The energy density is the prime parameter to define the deconfinement of quarks and gluons occurring in collisions of heavy ions. Recently, there is mounting evidence that many observables in proton-proton collisions behave in a manner very…
Carbon foams are hypothetical carbon allotropes that contain graphite-like (sp$^2$ carbon) segments, connected by sp$^3$ carbon atoms, resulting in porous structures. In this work the DFTB (Density Functional based Tight-Binding) method…