Related papers: Pressure induced structural and dynamical changes …
In this paper we present a new thermodynamically consistent phase transition model describing the evolution of a liquid substance, e.g., water, in a rigid container $\Omega$ when we freeze the container. Since the density $\varrho_{2}$ of…
We report a comprehensive structural and valence study of the intermediate valent materials YbNiGa$_{4}$ and YbNiIn$_{4}$ under pressures up to 60 GPa. YbNiGa$_{4}$ undergoes a smooth volume contraction and shows steady increase in…
The structure and the electronic properties of a sodium tetrasilicate (Na${}_2$Si${}_4$O${}_9$) glass were studied by combined Car-Parrinello and classical molecular-dynamics simulations. The glass sample was prepared using a method…
Recently for the first time a stable compound of He and Na (Na2He) is predicted at high pressure. We explore the pressure dependent elastic, mechanical and thermodynamic properties of this newly discovered Na2He by using ab initio…
The pressure-induced changes in the optical properties of $\beta$-Na$_{0.33}$V$_2$O$_5$ single crystals at room temperature were studied by polarization-dependent Raman and far-infrared reflectivity measurements under high pressure. From…
We study the slow dynamics of salol by varying both temperature and pressure using photon correlation spectroscopy and pressure-volume-temperature measurements, and compare the behavior of the structural relaxation time with equations…
Silica is the paradigmatic network glass-former and understanding its response to pressure is essential for comprehending the mechanical properties of silica-based materials and the behavior of silicate melts in the Earth's interior. While…
In the pressure range 5-12 GPa the fractional valence of cerium is independent of pressure because of the coexistence of two or more structural phases. The observation of a single crystallographic structure in this pressure range arises…
Pressure-induced changes in the Fermi surface of Cd up to 40 GPa are studied using highly accurate density-functional theory calculations. The topology of Fermi surface changes at pressures of 2, 8, 12 , 18 and 28 GPa indicating electronic…
We present the results of extensive molecular dynamics computer simulations in which the high frequency dynamics of silica, nu>0.5 THz, is investigated in the viscous liquid state as well as in the glass state. We characterize the…
We present in this paper the thermodynamics of superconducting PdH and PdD under pressure. We make use of a general method to calculate the thermodynamics under pressure within the Migdal-Eliashberg theory. We have considered the crystal…
Some results on damage build up in, and amorphization of, Si, induced by 25-30 keV Al$_5^-$, Si$_5^-$ and Cs$^-$ ions, at room temperature, are reported. We show that at low energy, amorphization is a nucleation and growth process, based on…
We investigated structural changes, phase diagram, and vibrational properties of hydrogen hydrate in filled-ice phase C2 by using first principles molecular dynamics simulation. It was found that the experimentally reported 'cubic'…
We present a computational study of the electronic properties of amorphous SiO2. The ionic configurations used are the ones generated by an earlier molecular dynamics simulations in which the system was cooled with different cooling rates…
Ab initio molecular dynamic method within the framework of density functional theory is applied to analyze the structural and electronic properties of crystalline molecular hydrogen at temperature 100\,K. Pressure, pair correlation function…
We study the thermodynamics of C incorporation on Si(100), a system where strain and chemical effects are both important. Our analysis is based on first-principles atomistic calculations to obtain the important lowest energy structures, and…
The time evolution of the pore size distributions and mechanical properties of amorphous solids at constant pressure is studied using molecular dynamics simulations. The porous glasses were initially prepared at constant volume conditions…
High pressure behaviour of superhydrous phase B(HT) of Mg10Si3O14(OH)4 (Shy B) is investigated with the help of density functional theory based first principles calculations. In addition to the lattice parameters and equation of state, we…
La$_3$Ni$_2$O$_7$ exists in two polymorphs: an unconventional structure with alternating layers of single- and triple-layered nickel-oxygen octahedra, and a classical double-layered Ruddlesden-Popper phase. In this study, we report the…
In this work the high pressure region of the phase diagram of water has been studied by computer simulation by using the TIP4P/2005 model of water. Free energy calculations were performed for ices VII and VIII and for the fluid phase to…