Higher-order topological insulators host gapless states on hinges or corners of three-dimensional crystals. Recent studies suggested that even topologically trivial may exhibit fractionally quantized charges localized at corners. Although most the previous focused two-dimensional systems, in this work, we take initial step toward systematic understanding hinge and corner insulators. We consider...

Two new tetrametallic lanthanide-phosphonate complexes have been structurally and magnetically characterised. The {Dy4} complex is a single molecule magnet.

We calculate the neutron incoherent scattering law due to a particle performing localized di!usional jumps in a con"ned environment of octahedral symmetry. An experimental realization for this model is provided by the fulleride Li 12 C 60 , where the Li ions di!use within the octahedral void determined by the surrounding C 60 spheres packed in a face centered cubic crystal structure. The result...

clusters are geographically close groups of related companies or institutions related to a certain area which are inherently more efficient than the other companies due to advantages such as being located in one place, networks, external knowledge, variability of human capital, etc. today, development through clusters plays a pivotal role in the economic and industrial policies of developed cou...

The Raman spectra of seven A(2)MWO(6) tungstate double perovskites are analysed. Ba(2)MgWO(6) is a cubic double perovskite with Fm3[combining macron]m symmetry and its Raman spectrum contain three modes that can be assigned in a straightforward manner. A fourth mode, the asymmetric stretch of the [WO(6)](6-) octahedron, is too weak to be observed. The symmetry of Ba(2)CaWO(6) is lowered to tetr...

Crystallization of diamond in the Mg-Si-C system has been studied at 7.5 GPa and 1800 ◦C with the Mg-Si compositions spanning the range from Mg-C to Si-C end-systems. It is found that as Si content of the system increases from 0 to 2 wt %, the degree of the graphite-to-diamond conversion increases from about 50 to 100% and remains at about this level up to 20 wt % Si. A further increase in Si c...

This article provides an overview of recent developments regarding synthesis of Pd nanocrystals with well-controlled shapes in aqueous solutions. In a solution-phase synthesis, the final shape taken by a nanocrystal is determined by the twin structures of seeds and the growth rates of different crystallographic facets. Here, the maneuvering of these factors in an aqueous system to achieve shape...

A systematic method is presented for constructing effective Hamiltonians for general phonon-related structural transitions. The key feature is the application of group theoretical methods to identify the subspace in which the effective Hamiltonian acts and construct for it localized basis vectors, which are the analogue of electronic Wannier functions. The results of the symmetry analysis for t...

A new hydrous silicate phase with formula Mg1.71Fe0.177Al0.01Si0.965H0.332O4 has been synthesized at 1400°C and 17.5GPa from a hydrous iron-rich mantle peridotite composition. The space group is Imma and unit cell parameters a = 5.6884(4); b = 28.9238(15); and c = 8.2382(6)Å, so that a and c are approximately those of wadsleyite, whereas b is 2.5 times that of wadsleyite. The calculated density...

The long elusive structure of Cu(II) hydrate in aqueous solutions, classically described as a Jahn-Teller distorted octahedron and recently proposed to be a fivefold coordination structure [Pasquarello et al., Science 291, 856 (2001)], has been probed with x-ray-absorption spectroscopy by performing a combined theoretical and experimental analysis. Two absorption channels were needed to obtain ...