LLNL researchers Tadashi Ogitsu and Eric Schwegler along with Giulia Galli of University of California, Davis, discuss in detail starting from the history of boron research, and the properties of β-boron, as inferred from experiments and the ab-initio theories developed over the last decade.
For all densities, we find a significant discrepancy between the ground state parametrized local density approximation and our results around the Fermi temperature. Our work based on Feynman paths can be used as a benchmark for developing finite-temperature density functionals, as well as input for orbital-free density function theory formulations.
The phase diagrams of MgSiO3 and MgO are studied from first-principles theory leading to evidence for a vast pressure-temperature regime where molten MgSiO3 decomposes into liquid SiO2 and solid MgO, with a volume change of approximately 1.2%. The demixing transition is driven by the crystallization of MgO - the reaction only occurs below the high-pressure MgO melting curve.
Model of the electronic wake (blue surfaces) generated by an energetic proton (red sphere) traveling in an aluminum crystal (yellow spheres). The resulting change in electronic density is responsible for modification of chemical bonds between the atoms and consequently for a change in their interactions.
The reaction mechanisms on the surface of bulk anatase TiO2 (101) and of a small TiO2 nano-cluster were investigated using first principles calculations. Significant barrier reduction observed on the nano-cluster surface is discussed in terms of how the under-coordinated titanium atoms and quantum confinement influence CO2 reduction kinetics at surface.
