Monoclinic YFe12 phases predicted from first principles

Novel superhard B-C-O phases predicted from first principles.

We explored the B-C-O system at pressures in the range 0-50 GPa by ab initio variable-composition evolutionary simulations in the hope of discovering new stable superhard materials. A new tetragonal thermodynamically stable phase B4CO4, space group I4[combining macron], and two low-enthalpy metastable compounds (B6C2O5, B2CO2) have been discovered. Computed phonons and elastic constants show th...

Highpressure phases of NaAlH4 from first principles

Related Articles Influence of monovalent ions on density fluctuations in hydrothermal aqueous solutions by small angle X-ray scattering J. Chem. Phys. 136, 044515 (2012) Nanoscale diffraction imaging of the high-pressure transition in Fe1−xO Appl. Phys. Lett. 100, 041903 (2012) High-pressure study of tetramethylsilane by Raman spectroscopy J. Chem. Phys. 136, 024503 (2012) High-pressure optical...

Phases of Ca from first principles.

Structures and properties of many of the phases of Ca under pressure are calculated from first principles by a systematic procedure that minimizes total energy E with respect to structure under the constraint of constant volume V. The minima of E are followed on successive sweeps of lattice parameters for 11 of 14 Bravais symmetries for one-atom-per-cell structures. The structures include the f...

A Massive Core in Jupiter Predicted From First-Principles Simulations

Hydrogen-helium mixtures at conditions of Jupiter’s interior are studied with first-principles computer simulations. The resulting equation of state (EOS) implies that Jupiter possesses a central core of 14 – 18 Earth masses of heavier elements, a result that supports core accretion as standard model for the formation of hydrogen-rich giant planets. Our nominal model has about 2 Earth masses of...

Stability trends of MAX phases from first principles