Computational prediction of novel two-dimensional tungsten nitride superconductors.

Transition metal nitrides are well-known 3D superconductor materials. However, there is a lack of knowledge related to their two-dimensional (2D) counterparts, which have several potential technological applications. In this work, we predict, using an evolutionary algorithm coupled with a first-principles approach, a set of novel 2D superconductive structures based on tungsten nitride.

Electronic and optical competence of TiO/BiVO nanocomposites in the photocatalytic processes.

Nanocomposites with different ratios of titanium dioxide and bismuth vanadate [TiO]/[BiVO] give rise to compatible electronic band structure alignment at their interfaces to ensure enhanced photoactivated charge transfer under visible light. The sol-gel method and suitable post-synthesis thermal treatments were used to synthesize different compositions with stabilized anatase phase of TiO and monoclinic scheelite polymorph BiVO. Structural, electronic and optical characterizations were performed and the results were analysed as a function of the stoichiometry, in which both crystalline structures show a clear junction formation among their characteristic stacking planes.

Comparing two high correlation models to test the mechanical stability of americium-II.

In this work two high density functional theory (DFT) correlation methodologies, the so called DFT+U (or GGA+U) implementation and the exact exchange of correlated electrons (EECE), hybrid DFT functional (or one case of hybrid DFT), are tested to determine the mechanical properties of americium-II. For each case, the numeric value of their principal parameter is chosen ([Formula: see text] for the first case and [Formula: see text] for the second one) once the crystalline structure meets all the mechanical stability conditions. The results show that there is a range of values of [Formula: see text] and [Formula: see text] in which both methodologies generate a stable (experimentally correct) non-magnetic ground state, reaching approximately the same numeric value of the set of elastic constants of the cubic structure.