Related papers: Short-range order stabilizes a cubic Fe alloy in E…
Understanding the structure and dynamics of Earth's inner core is essential for constraining its composition, thermal evolution, and seismic properties. Silicon is a probable major component of Earth's core. Using first-principles molecular…
The crystal structure of iron in the Earth's inner core remains debated. Most recent experiments suggest a hexagonal-close-packed (hcp) phase. In simulations, it has been generally agreed that the hcp-Fe is stable at inner core pressures…
Earth's inner core exhibits an unusually high Poisson's ratio and noticeable elastic anisotropy. The mechanisms responsible for these features are critical for understanding the evolution of the Earth but remain unclear. This study…
Seismic observations show a reduced compressional-wave gradient at the base of the outer core relative to the preliminary reference Earth model and seismic wave asymmetry between the east-west hemispheres at the top of the inner core. Here,…
The Fe-Ni alloy is believed to be the main component of Earth's core. Yet, a comprehensive understanding of phase equilibria near the melting point of this alloy under core conditions is still lacking, leaving the effect of nickel…
Using evolutionary crystal structure prediction algorithm USPEX, we identify the compositions and crystal structures of stable compounds in the Fe-S system at pressures in the range 100-400 GPa. We find that at pressures of the Earth's…
The structure and stability of iron near melting at multi-megabar pressures are of significant interest in high pressure physics and earth and planetary sciences. While the body-centered cubic (BCC) phase is generally recognized as unstable…
Ni is the second most abundant element in the Earth's core. Yet, its effects on the inner core's structure and formation process are usually disregarded because of its electronic and size similarity with Fe. Using ab initio molecular…
The Fe-O system is fundamental to understanding the composition and properties of the Earth's core. Recent studies have suggested the possible existence of stable, iron-rich FenO compounds at around 215 GPa. Here, we performed…
The crystallographic structure of iron under extreme conditions is a key benchmark for cutting-edge experimental and numerical methods. Moreover, it plays a crucial role in understanding planetary cores, as it significantly influences the…
There has been a long debate on the stable phase of iron under the Earth's inner core conditions. Because of the solid-liquid coexistence at the inner core boundary, the thermodynamic stability of solid phases directly relates to their…
Mixtures of bare atomic nuclei on a nearly uniform degenerate electron background are a realistic model of matter in the interior of white dwarfs. Despite tremendous progress in understanding their phase diagrams achieved mainly via…
We study the phase behaviour of the Al$_x$CrFeCoNi high-entropy alloy. Our approach is based on a perturbative analysis of the internal energy of the paramagnetic solid solution as evaluated within the Korringa-Kohn-Rostoker formulation of…
It has long been assumed the Earth's solid inner core started to grow when molten iron cooled to its melting point. However, the nucleation mechanism, which is a necessary step of crystallization, has not been well understood. Recent…
The improvements of the knowledge of the seismic structure of the inner core and the complexities thereby revealed ask for a dynamical origin. Sub-solidus convection was one of the early suggestions to explain the seismic anisotropy, but it…
Short-range order (SRO) in disordered alloys is typically interpreted as competition between chemical effect of negative (or positive) energy gain by mixing constituent elements and geometric effects comes from difference in effective…
Seismic observations of a slowdown in P wave velocity at the base of Earth's outer core suggest the presence of a stably-stratified region known as the F-layer. This raises an important question: how can light elements that drive the…
We employ state-of-the-art ab initio simulations within the dynamical mean-field theory to study three likely phases of iron (hexogonal close-packed, hcp, face centered cubic, fcc, and body centered cubic, bcc) at the Earth's core…
The physical process creating layered structure in planetary rocky bodies is considered here to be multicomponent solidification. This is a unified alternative approach to the present interpretations where each layer is reasoned and matched…
Using an atom-vacancy exchange algorithm, we investigate the kinetics of the order-disorder transition in an fcc A_3B binary alloy model following a temperature quench from the disordered phase. We observe two clearly distinct ordering…