Related papers: Carbon Nitride Frameworks and Dense Crystalline Po…
We have studied dense hydrogen and deuterium experimentally up to 320 GPa and using ab initio molecular dynamic (MD) simulations up to 370 GPa between 250 and 300 K. Raman and optical absorption spectra show significant anharmonic and…
Novel cubic allotrope yne-C$_{16}$ with sp$^3$/sp$^1$ carbon hybridizations is devised based on crystal chemistry and computations of the ground structure and the energy-dependent quantities within the quantum density functional theory DFT.…
The ability to reliably predict the structures and stabilities of a molecular crystal and its polymorphs without any prior experimental information would be an invaluable tool for a number of fields, with specific and immediate applications…
This paper summarizes 0 GPa to 0.6 GPa neutron diffraction measurements of a nickel hexacyanochromate coordination polymer (NiCrPB) that has the face-centered cubic, Prussian blue structure. Deuterated powders of NiCrPB contain ~100 nm…
The pressure-induced polymorphism of binary octect compounds has long been considered a settled problem although the possible atomic disordering of some phases remains a puzzling observation. Taking GaP as a case study, we conclude, through…
In this work we describe the thermodynamics and mechanism of CO$_2$ polymorphic transitions under pressure from form I to form III combining standard molecular dynamics, well-tempered metadynamics and committor analysis. We find that the…
A layered rhombohedral polymorph of indium (III) triiodide is synthesized at high pressure and temperature. The unit cell symmetry and approximate dimensions are determined by single crystal X-ray diffraction. Its R-3 crystal structure,…
A new 3d-5d hybridized quadruple perovskite oxide, CaCu3Mn2Ir2O12, was synthesized by high-pressure and high-temperature methods. The Rietveld structure analysis reveals that the compound crystallizes in an AA'3B4O12-type perovskite…
Nitrides in many ways are fascinating since they often appear as superconductors, high energy density and hard materials. Though there exist a large variety of nitrides, noble gas nitrides are long missing in nature. Pursuit of noble gas…
The paper presents results of a comprehensive study from first principles into the properties of Ni, Pd, Rh, and Ir crystals under pressure. We calculated elastic constants, phonon spectra, isotherms, Hugoniots, sound velocities, relative…
We map the high-pressure phase diagram of nitrogen hydrate up to 16 GPa at room temperature by combining neutron diffraction, Raman spectroscopy, and crystal structure prediction. We reveal a rich sequence of structural transformations,…
From crystal chemistry rationale and density functional DFT calculations, novel tetragonal carbon C5 is proposed as simplest ultrahard allotrope with mixed hybrid carbon hybridizations (sp2 - sp3). Novel pentacarbon is identified as…
Raman spectroscopy has been the most extensively employed method to study carbon nanotubes at high pressures. This review covers reversible pressure-induced changes of the lattice dynamics and structure of single- and multi-wall carbon…
We investigate the magnetic structure of Mn3-xFexSn2 using neutron powder diffraction experiments and electronic structure calculations. These alloys crystallize in the orthorhombic Ni3Sn2 type of structure (Pnma) and comprise two…
We report experimental evidence for pressure instabilities in the model multiferroic BiFeO3 and namely reveal two structural phase transitions around 3 GPa and 10 GPa by using diffraction and far-infrared spectroscopy at a synchrotron…
In this paper, three novel metallic sp2/sp3 -hybridized Boron Nitride (BN) polymorphs are proposed by first-principles calculations. One of them, named as tP-BN, is predicted based on the evolutionary particle swarm structural search. tP-BN…
Modeling the atomic structure of amorphous materials has long been a critical challenge in materials science. Recent advances in monolayer amorphous materials enable direct observation of their atomic structures, paving the way for a better…
A comparative computational study of stability of candidate structures for an as yet unknown silver dichloride AgCl2 is presented. It is found that all considered candidates have a negative enthalpy of formation, but are unstable towards…
It is suggested that the substitutional nitrogen in diamonds bonded to three of the surrounding carbon atoms instead of four. This proposed electron configuration of the defect is deduced from previous experiments and theoretical…
Knorringite, the Cr-end-member of the pyrope garnet series (Nixon et al. 1968), often occur in high proportions in kimberlite garnets and is thus used for tracing high-pressure deep-earth conditions favorable to the formation of diamonds,…