Related papers: Unconventional phase III of high-pressure solid hy…
We investigate the distorted face-centered-cubic (dfcc) phase of yttrium (Y) using a data-assimilation-based structure search that combines high-resolution powder x-ray diffraction (XRD) data with machine-learning interatomic potentials. By…
We test the performance of a recently proposed fundamental measure density functional of aligned hard cylinders by calculating the phase diagram of a monodisperse fluid of these particles. We consider all possible liquid crystalline…
A theoretical study is reported of the molecular-to-atomic transition in solid hydrogen at high pressure. We use the diffusion quantum Monte Carlo method to calculate the static lattice energies of the competing phases and a…
The phase diagram of hydrogen is one of the most important challenges in high-pressure physics and astrophysics. Especially, the melting of dense hydrogen is complicated by dimer dissociation, metallization and nuclear quantum effect of…
The term "MAX phase" refers to a very interesting and important class of layered ternary transition-metal carbides and nitrides with a novel combination of both metal and ceramic-like properties that have made these materials highly…
A new phase field crystal (PFC) type theory is presented, which accounts for the full spectrum of solid-liquid-vapor phase transitions within the framework of a single density order parameter. Its equilibrium properties show the most…
Hard helices can be regarded as a paradigmatic elementary model for a number of natural and synthetic soft matter systems, all featuring the helix as their basic structural unit: from natural polynucleotides and polypeptides to synthetic…
Constructing an accurate atomistic model for the high-pressure phases of tin (Sn) is challenging because properties of Sn are sensitive to pressures. We develop machine-learning-based deep potentials for Sn with pressures ranging from 0 to…
We propose three new phases of H2O under ultrahigh pressure. Our structural search was performed using an adaptive genetic algorithm which allows an extensive exploration of crystal structure. The new sequence of pressure-induced…
We predict a new candidate high-temperature high-pressure structure of FeSiO$_3$ with space-group symmetry Cmmm by applying an evolutionary algorithm within DFT+U that we call post-perovskite II (PPv-II). An exhaustive search found no other…
By performing constant-pressure variable-cell ab initio molecular dynamics simulations we find a quadrupolar orthorhombic structure, of $Pca2_1$ symmetry, for the broken symmetry phase (phase II) of solid H2 at T=0 and P =110 - 150 GPa. We…
Structural evolution of a prospective hydrogen storage material, ammonia borane NH3BH3, has been studied at high pressures up to 12 GPa and at low temperatures by synchrotron powder diffraction. At 293 K and above 1.1 GPa a disordered I4mm…
We study the electronic excitation spectra in solid molecular hydrogen (phase I) at ambient temperature and 5-90 GPa pressures using Quantum Monte Carlo methods and Many-Body Perturbation Theory. In this range, the system changes from a…
Molecular dynamics is a powerful method for studying the behaviour of materials at high temperature. In practice, however, its effectiveness in representing real systems is limited by the accuracy of the forces, finite size effects,…
We investigate the ${\rm H_3S}$ phase of sulphur hydride under high pressure $\simeq$ 200 GPa by means of {\it ab-initio} calculations within the framework of the density-functional theory (DFT) with the PBE0 hybrid exchange-correlation…
Samarium hydrides, belonging to the broad class of lanthanide polyhydrides, have yet to be experimentally tested at high pressure. In this study, we use random structure searches to explore multiple possible stoichiometries and propose…
We have performed first principles study for bismuth crystal structure at pressure from 0~14 GPa based on structure search and quasi-harmonic approximation. A new stable phase with Pbcm symmetry is predicted by structure search method. We…
Constructed to satisfy all known exact constraints and appropriate norms for a semilocal density functional, the strongly constrained and appropriately normed (SCAN) meta-generalized gradient approximation functional has shown early promise…
We present computer simulations of liquid and solid phases of condensed methane at pressures below 25 GPa, between 150 and 300 K, where no appreciable molecular dissociation occurs. We used molecular dynamics (MD) and metadynamics…
The antipolar $Pbcn$ phase of HfO$_2$ has been suggested to play an important role in the phase transition and polarization switching mechanisms in ferroelectric hafnia. In this study, we perform a comprehensive benchmark of density…