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High-quality epitaxial growth of inter-metallic MnPt films on oxides is achieved, with potential for multiferroic heterostructure applications. Antisite-stabilized spin-flipping induces ferromagnetism in MnPt films, although it is robustly antiferromagnetic in bulk. Moreover, highly ordered antiferromagnetic MnPt films exhibit superiorly large exchange coupling with a ferromagnetic layer.

Topological materials are derived from the interplay between symmetry and topology. Advances in topological band theories have led to the prediction that the antiperovskite oxide Sr3 SnO is a topological crystalline insulator, a new electronic phase of matter where the conductivity in its (001) crystallographic planes is protected by crystallographic point group symmetries. Realization of this material, however, is challenging. Guided by thermodynamic calculations, a deposition approach is designed and implemented to achieve the adsorption-controlled growth of epitaxial Sr3 SnO single-crystal films by molecular-beam epitaxy (MBE). In situ transport and angle-resolved photoemission spectroscopy measurements reveal the metallic and electronic structure of the as-grown samples. Compared with conventional MBE, the used synthesis route results in superior sample quality and is readily adapted to other topological systems with antiperovskite structures. The successful realization of thin films of Sr3 SnO opens opportunities to manipulate topological states by tuning symmetries via strain engineering and heterostructuring.

8 Shapeand size-control of nanocrystals (NCs) is valuable in many aspects of modern science and technology. [ 1–9 ] Wet chemical methods are widely used in the synthesis of metal, metal oxide, and metal sulfi de NCs with various shapes and dimensions in a controllable manner. [ 1–9 ] However, they are unsuitable for the synthesis of carbides and nitrides because of their high melting points (generally > 2000 ° C) as well as a lack of appropriate precursors. Carbide and nitride NCs are of signifi cant interest for biomedical applications and optical devices operated in extreme conditions, because they have high strength and unique optical properties while being chemically inert and biocompatible. [ 10–15 ] The properties of NCs are dependent on not only their constituent materials but also their geometries. Nanorings, for example, are important zero-dimensional nanostructures in many applications and they provide an excellent model to explore quantum-related properties. [ 16–19 ] Their fabrication, however, remains a signifi cant challenge using existing fabrication methodologies. [ 20–22 ]

Magnetic excitation of the iron-based superconductor parent compound BaFe2As2 at finite temperature are addressed with a first-principles formulation of the Helmholtz energy, which can account for the finite temperature mixture of many magnetic configurations. We find that it is the spin exchange coupling in the interplane c direction that dictates the spin density wave ordering. We have also quantitatively predicted the pressure dependence of the spin density wave ordering temperature, the Schottky anomaly, and the temperature dependence of thermal populations of several low-energy spin configurations, all in agreement with available experimental data. V C 2010 Wiley Periodicals, Inc. Int J Quantum Chem 111: 3565-3570, 2011

A Na-ion solid-state electrolyte, Na3 P0.62 As0.38 S4 , is developed with an exceptionally high conductivity of 1.46 mS cm-1 at 25 °C and enhanced moisture stability. Dual effects of alloying element As (lattice expansion and a weaker AsS bond strength) are responsible for the superior conductivity. Improved moisture stability is regulated by shifting low-energy moisture reactions to high-energy ones due to As.

The binary Ba–Ni and Ba–Ti systems are modeled by computational thermodynamics using the CALculation of PHAse Diagram (CALPHAD) method, wherein the thermodynamic parameters of disordered bcc, fcc and hcp phases are evaluated in terms of the first-principles calculations using the special quasirandom structures (SQSs). In combination with the Ni–Ti system modeling in the literature, the phase equilibria of the Ba–Ni–Ti system are predicted. Isothermal section of the ternary system is presented.