Order-Disorder Phase Transition and Ionic Conductivity in a LiBH Solid Electrolyte.

Temperature-induced phase transitions and ionic conductivities of LiBH and LiCBH were simulated with the use of machine learning interatomic potentials based on van der Waals-corrected density functional theory (rev-vdW-DF2 functional). The simulated temperature of order-disorder phase transition, lattice parameters, diffusion, ionic conductivity, and activation energies are in good agreement with experimental data. Our simulations of LiBH uncover the importance of the reorientational motion of the [BH] anion.

Ultralow reaction barriers for CO oxidation in Cu-Au nanoclusters.

Systematic structure prediction of CuAu nanoclusters was carried out for a wide compositional area ( + ≤ 15) using the evolutionary algorithm USPEX and DFT calculations. The obtained structural data allowed us to assess the local stability of clusters and their suitability for catalysis of CO oxidation. Using these two criteria, we selected several most promising clusters for an accurate study of their catalytic properties.

Density Functional Theory Modeling of Reactions of Addition of H Molecules to Magnesium Clusters MgM Doped with Atoms M of Transition 3d Elements.

Density functional theory calculations of potential energy surface (PES) have been performed for elementary hydrogenation reactions MgM + H → MgMH of magnesium clusters MgM doped by transition 3d metals (M = Ti-Ni), and for consecutive reactions MgNi + H → MgNiH of addition of hydrogen molecules to Ni-doped clusters MgNi and MgNiH. Energetic, geometric, and spectroscopic features of intermediates and transition states along the minimum energy pathway have been found, and their trends were analyzed with dopants changing along the 3d series and with increasing number of atoms H attached to the surface positions of the magnesium backbone.