A structure is proposed for the hexagonal form of MnAl(4), with a(H) = 28.4 A and c(H) = 12.43 A, on the basis of a high-resolution electron micrograph and comparison with crystals of known structures. The proposed structure involves seven 104-atom complexes of 20 Friauf polyhedra, sharing some atoms with one another. It is closely related to the 23.36-A cubic structure of MnAl(4) and to the 14...

Black phosphorus was compressed at room temperature across the A17, A7 and simple-cubic phases up to 30 GPa, using a diamond anvil cell and He as pressure transmitting medium. Synchrotron X-ray diffraction showed the persistence of two previously unreported peaks related to the A7 structure in the pressure range of the simple-cubic phase. The Rietveld refinement of the data demonstrates the occ...

We study the level-expansion structure of the NS string field theory actions, mainly focusing on the modified (i.e. 0-picture in the NS sector) cubic superstring field theory. This theory has a non-trivial structure already at the quadratic level due to presence of the picture-changing operator. It is explicitly shown how the usual Maxwell and tachyon actions can be obtained after integrating o...

The electron density distribution of the solvent in the cubic insulin crystal structure, which occupies 65% of the volume, has been mapped from 1.7-A resolution diffraction data by an iterative difference Fourier method, using the previously determined protein structure as the refinement restraint. Starting with phases from the protein and a flat solvent model, the difference map calculated fro...

Optical transmission spectrum measurements in an electric field are used to study the short-range structure of the blue phase III (BPIII). The data are compared with the theoretical models for BPIII. Our results can be explained by the models in which BPIII has the simple-cubic local structure or cubic bond orientational order.

The emergence of topologically protected conducting states with the chiral spin texture is the most prominent feature at the surface of topological insulators. On the application side, large band gap and high resistivity to distinguish surface from bulk degrees of freedom should be guaranteed for the full usage of the surface states. Here, we suggest that the oxide cubic perovskite YBiO3, more ...

Ž . Ž . The growth of cubic aluminum nitride AlN and cubic gallium nitride GaN is studied. The effects of ambient pressure and substrate temperature on the structure of the AlN and GaN films are systematically investigated. It is shown that the films are amorphous when the temperature and the pressure are too low. Cubic AlN is obtained at a temperature of 8008C and a pressure of 0.2 Torr. Cubic...

Results based on ab initio density functional calculations indicate that cubic diamond, boron nitride, and many other cubic structures including rocksalt share a general graphitization tendency in ultrathin films terminated by close-packed (111) surfaces. Whereas such compounds often show an energy preference for cubic rather than layered atomic arrangements in the bulk, the surface energy of l...