Related papers: Novel phases in the Fe-Si-O system at terapascal p…
We use ab initio global structural prediction, and specifically the minima hopping method, to explore the periodic table in search of novel oxide phases. In total, we study 183 different compositions of the form MXO2, where M=(Cu, Ag, Au)…
The recent discovery and subsequent developments of FeAs-based superconductors have presented novel challenges and opportunities in the quest for superconducting mechanisms in correlated-electron systems. Central issues of ongoing studies…
The structural and magnetic phase transitions of the ternary iron arsenides SrFe2As2 and EuFe2As2 were studied by temperature-dependent x-ray powder diffraction and 57-Fe Moessbauer spectroscopy. Both compounds crystallize in the tetragonal…
The stability of ($R$, Zr)(Fe, Co, Ti)$_{12}$ with a ThMn$_{12}$ structure is investigated using first-principles calculations. We consider energetic competition with multiple phases that have the Th$_2$Zn$_{17}$ structure and the unary…
Changes in atomic coordination numbers at high pressures are fundamental to condensed-matter physics because they initiate the emergence of unexpected structures and phenomena. Silicon is capable of forming eight-, nine-, and…
The elastic and magnetic properties, thermodynamical stability, deviation from stoichiometry and order/disorder transformations of phases that are relevant to Be alloys were investigated using density functional theory simulations coupled…
First-principles simulations have been performed to investigate the phase stability of tantalum metal under high pressure and high temperature (HPHT). We searched its low-energy structures globally using our developed multi-algorithm…
While the tetragonal antiferro-electrically distorted (AFD) phase with space group $I4/mcm$ is well known for SrTiO$_3$ to occur below 105 K, there are also some hints in literature of an orthorhombic phase, either at lower temperature at…
Based on a previously proposed thermodynamic analysis, we study the relative stabilities of five Si phases under uniaxial compression using ab initio methods. The five phases are diamond, beta-tin, sh, sc, and hcp structures. The possible…
As structural and functional materials, topologically close-packed (TCP) phases of transition metal compounds offer a wide range of attractive properties. Due to their complex crystal structure and the resulting brittleness, the knowledge…
Properties of the $\omega$ structure are investigated for 27 transition elements from the viewpoints of thermodynamical and mechanical stability based on first-principles calculations. The thermodynamical stability of the $\omega$ structure…
We report on the synthesis of superconducting single crystals of FeSe, and their characterization by X-ray diffraction, magnetization and resistivity. We have performed ac susceptibility measurements under high pressure in a hydrostatic…
Lanthanum, yttrium, and cerium hydrides are the three most well-known superconducting binary hydrides (La-H, Y-H, and Ce-H systems), which have gained great attention in both theoretical and experimental studies. Recent studies have shown…
We investigate the stability of the multipolar orderings in $f$-electron material CeCoSi based on a self-consistent mean-field calculation for the effective localized model. This material has two ordered phases in the temperature-pressure…
Here, we provide a detailed study of the crystal structure and physical properties of the recently discovered vdW ferromagnet FePd$_2$Te$_2$. We find this compound has a relatively wide width of formation, and grow single crystals with…
Novel wide-band-gap semiconductors are needed for next-generation power electronic but there is a gap between a promising material and a functional device. Finding stable contacts is one of the major challenges, which is currently dealt…
The archetypal $3d$ Mott insulator hematite, Fe$_2$O$_3$, is one of the basic oxide components playing an important role in mineralogy of Earth's lower mantle. Its high pressure-temperature behavior, such as the electronic properties,…
Superionic states are phases of matters that can simultaneously exhibit some of the properties of a fluid and of a solid. Superionic states of ice, H$_{3}$O, He-H$_{2}$O or He-NH$_{3}$ compounds have been reported in previous works.…
Group I/II materials exhibit unexpected structural phase transitions at high pressures, providing potential insight into the origins of elemental superconductivity. We present here a computational study of elemental barium and binary…
Using density-functional-theory calculations, we have identified new stable configurations for tri-, tetra-, and penta-vacancies in silicon. These new configurations consist of combinations of a ring-hexavacancy with three, two, or one…