Related papers: Stability and metallization of solid oxygen under …
Using ab initio evolutionary simulations, we explore all the possible stoichiometries for Mg-O system at pressures up to 850 GPa. In addition to MgO, our calculations find that two extraordinary compounds MgO2 and Mg3O2 become…
The simple alkali metal Na, that crystallizes in a body-centred cubic structure at ambient pressure, exhibits a wealth of complex phases at extreme conditions as found by experimental studies. The analysis of the mechanism of stabilization…
Phase stability, and the limits thereof, are a central concern of materials thermodynamics. However, the temperature limits of equilibrium liquid stability in chemical systems have only been widely characterized under constant (typically…
Hafnia (HfO2) is a silicon-compatible dielectric material, yet stabilizing its desired but metastable ferroelectric phase remains challenging. Phase stability predictions by density functional theory (DFT) have provided crucial guidance,…
Despite the common expectation that conjugated organic molecules on metals tend to adsorb in a flat-lying wetting layer, several recent studies have found strong indications for coverage-dependent transitions to upright-standing phases,…
A series of electronic and structural transitions are predicted in molten lithium from first principles. A new phase with tetrahedral local order characteristic of $sp^3$ bonded materials and poor electrical conductivity is found at…
Identifying the atomic structure and properties of solid hydrogen under high pressures is a long-standing problem of high-pressure physics with far-reaching significance in planetary and materials science. Determining the…
Atomic metallic hydrogen has been produced in the laboratory at high pressure and low temperature, prompting further investigations of its different properties. However, purely experimental approaches are infeasible because of the extreme…
In the present paper we generalised a phenomenological model developed in \cite{gomo:2005} for the description of magnetostructural phase transitions and related peculiarities of elastic properties in solid oxygen under high pressure and/or…
A vast amount of Raman spectroscopic data, obtained using diamond anvil cell technique under in situ high pressure-temperature conditions, has been used for mapping the phase transitions of hydrogen in the temperature range of 300 K to 900…
We investigate via quantum molecular-dynamics simulations the thermophysical properties of shocked liquid ammonia up to the pressure 1.3 TPa and temperature 120000 K. The principal Hugoniot is predicted from wide-range equation of state,…
Layered $\alpha$-In$_2$Se$_3$has been studied using a concomitant in-situ synchrotron angle dispersive powder x-ray diffraction and Raman spectroscopy study in a diamond anvil cell up to 60+ GPa, at room temperature. Helium, that remains…
High pressure behaviour of liquid GeO2 is investigated by means of molecular dynamics simulations in the pressure range 0-20 GPa and at various temperatures. In agreement with the recent experiments (PRL, 92, 155506, 2004), Ge-O…
Carbon monoxide and nitrogen are among the potentially interesting high-energy density materials. However, in spite of the physical similarities of the molecules, they behave very differently at high pressures. Using density functional…
Diatomic nitrogen is an archetypal molecular system known for its exceptional stability and complex behavior at high pressures and temperatures, including rich solid polymorphism, formation of energetic states, and an insulator-to-metal…
A systematic ab initio search for low enthalpy phases of disilane (Si_2H_6) at high pressures was performed based on the minima hopping method. We found a novel metallic phase of disilane with Cmcm symmetry, which is enthalpically more…
We present a Tight-Binding Molecular Dynamics investigation of the stability, the geometrical and the electronic structure of suspended monatomic transition metal chains. We show that linear and stable monatomic chains are formed at…
According to the theoretical predictions, insulating molecular hydrogen dissociates and transforms to an atomic metal at pressures P~370-500 GPa. In another scenario, the metallization first occurs in the 250-500 GPa pressure range in…
Phase behaviors of two-dimensional (2D) systems constitute a fundamental topic in condensed matter and statistical physics. Although hard polygons and interactive point-like particles are well studied, the phase behaviors of more realistic…
The equation of state, structural behavior and phase stability of {\alpha}-uranium have been investigated up to 1.3 TPa using density functional theory, adopting a simple description of electronic structure that neglects the spin-orbit…