Related papers: Predicted Complex Lithium Phases at Terapascal Pre…
The B-Pt alloy system contains several Pt-rich phases exhibiting complex structures, many with partial site occupation. It also exhibits a deep (nearly 1000 degrees C) eutectic. We evaluate the ab-initio total energies of the crystalline…
The paper presents ab initio results on the structural phase stability of beryllium and magnesium crystals under high and ultrahigh pressures (multi-terapascal regime). Magnesium is shown to undergo a number of structural transformations…
A first-principles-derived approach is used to study structural, piezoelectric and dielectric properties of Pb(Zr_{1-x}Ti_{x})O_{3} (PZT) solid solutions near the morphotropic phase boundary at low temperature. Three ferroelectric phases…
All-solid-state batteries are expected to enable batteries with high energy density with the use of lithium metal anodes. Although solid electrolytes are believed to be mechanically strong enough to prevent lithium dendrites from…
We study the electronic and lattice dynamical properties of compressed solid germane in the pressure range up to 200 GPa with density functional theory. A stable metallic structure, Aba2, with a base-centered orthorhombic symmetry was found…
High pressure in-situ synchrotron X-ray diffraction experiments were performed on Ag2Te up to 42.6 GPa at room temperature and four phases were identified. Phase I ({\beta}-Ag2Te) transformed into phase II at 2.4 GPa, and phase III and…
The whole Al-Li phase diagram is predicted from first principles calculations and statistical mechanics including the effect of configurational and vibrational entropy. The formation enthalpy of different configurations at different…
In this study, ultrasonic measurements were performed on a single crystal of cubic PrNi$_2$Cd$_{20}$, down to a temperature of 0.02 K, to investigate the crystalline electric field ground state and search for possible phase transitions at…
Two novel room-temperature phase transitions are observed, via synchrotron x-ray diffraction and Raman spectroscopy, in the Pb(Zr0.52Ti0.48)O3 alloy under hydrostatic pressures up to 16 GPa. A monoclinic (M)-to-rhombohedral (R1) phase…
We develop a unified view of topological phase transitions (TPTs) in solids by revising the classical band theory with the inclusion of topology. Re-evaluating the band evolution from an "atomic crystal" [a normal insulator (NI)] to a solid…
Hydrogen-rich compounds are important for understanding the dissociation of dense molecular hydrogen, as well as searching for room temperature Bardeen-Cooper-Schrieffer (BCS) superconductors. A recent high pressure experiment reported the…
Titanium dioxide has been extensively studied in the rutile or anatase phases, while its high-pressure phases are less well understood, despite that many are thought to have interesting optical, mechanical and electrochemical properties.…
This paper investigates some of the successes and failures of density functional theory in the study of high-pressure solid hydrogen at low temperature. We calculate the phase diagram, metallization pressure, phonon spectrum, and proton…
Based on its simple valence electron configuration, we may expect lithium to have straightforward physical properties that are easily explained. However, solid lithium, when cooled below 77 K, develops a complex structure that has been…
Recent advances in Generalized Ensemble simulations and microcanonical analysis allowed the investigation of structural transitions in polymer models over a broad range of local bending and torsion strengths. It is reasonable to argue that…
Polymorphic solids of the same chemical composition can have different atomic structures; in each polymorph atoms vibrate around a local potential energy minimum (LPEM). If transformations to other structures have sufficiently high enthalpy…
Understand the nature of liquid structure and its evolution under different conditions is a major challenge in condensed physics and materials science. Here, we report a pressure-induced structure change spanning a wide pressure range in…
We have used ab-initio density functional theory technique to understand the phase transitions and structural changes in various high temperature/pressure phases of LiAlO2. The electronic band structure as well as phonon spectra are…
The physical properties of plutonium and plutonium-based intermetallic compounds are extremely sensitive to temperature, pressure, and chemical alloying. A celebrated example is the high-temperature $\delta$ phase plutonium, which can be…
X-ray diffraction (XRD) experiments have been carried out on quartz-like GaPO4 at high pressure and room temperature. A transition to a high pressure disordered crystalline form occurs at 13.5 GPa. Slight heating using a YAG infrared laser…