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For any thorough investigation of complex physical properties, as encountered in strongly correlated electron systems, not only single crystals of highest quality but also a detailed knowledge of the structural properties of the material are pivotal prerequisites. Here, we combine physical and chemical investigations on the prototypical heavy fermion superconductors CeIrIn5 and CeCoIn5 on atomic and macroscopic length scale to gain insight into their precise structural properties. Our approach spans from enhanced resolution X-ray diffraction experiments to atomic resolution by means of scanning tunneling microscopy (STM) and reveal a certain type of local features (coexistence of minority and majority structural patterns) in the tetragonal HoCoGa 5-type structure of both compounds.

The thermoelectric performance of EuCd2Sb2 and YbCd2Sb2 was improved by mixed cation occupation. The composition, structure, and thermoelectric properties of YbxEu1-xCd2Sb2 (x=0, 0.5, 0.75, and 1) have been investigated. Polycrystalline samples are prepared by direct reaction of the elements. Thermoelectric properties were investigated after densification of the materials by spark plasma sintering. YbxEu1-xCd2Sb2 crystallizes in the P3m1 space group. The lattice parameters increase with the europium content. These materials show low electrical resistivity, high Seebeck coefficient, and low thermal conductivity together with high carrier concentration and high carrier mobility. ZT values of 0.88 and 0.97 are obtained for Yb0.5Eu0.5Cd2Sb2 and Yb0.75Eu0.25Cd2Sb2 at 650 K, respectively. [ABSTRACT FROM AUTHOR]

Rare earth metal borides have attracted great interest due to their unusual properties, such as superconductivity and f-electron magnetism. A recent discovery attributes the tunability of magnetism in rare earth aluminoborides to the effect of so-called "building defects." In this paper, we report data for the effect of building defects on the thermal conductivities of α-TmAlB4 single crystals. Building defects reduce the thermal conductivity of α-TmAlB4 by ≈30%. At room temperature, the thermal conductivity of AlB2 is nearly a factor of 5 higher than that of α-TmAlB4. AlB2 single crystals are thermally anisotropic with the c-axis thermal conductivity nearly twice the thermal conductivity of the a-b plane. Temperature dependence of the thermal conductivity near and above room temperature reveals that both electrons and phonons contribute substantially to thermal transport in AlB2 with electrons being the dominant heat carriers. [ABSTRACT FROM AUTHOR]

The electron localizability indicator in momentum space is proposed as a functional of the same-spin momentum pair density. This functional yields a discrete distribution of values, which are proportional to the charge needed to form a fixed very small fraction of a same-spin electron pair. It resolves all atomic shells for the examined atoms (Li–Kr) with reasonable occupation numbers, especially in the valence region. © 2006 Wiley Periodicals, Inc. Int J Quantum Chem, 2006 [ABSTRACT FROM AUTHOR]

The essence of new technological mode in the world economy, some features of innovative development of the mineral complex and the nickel industry, dynamics of world production and consumption of nickel have been considered. The organization and economic structure of the nickel industry in Russia has been characterized. The prospects for sustainable development of the nickel industry in conditions of the sixth technological mode have been justified. Рассмотрены сущность нового технологического уклада в мировой экономике, особенности инновационного развития минерально-сырьевого комплекса и никелевой промышленности, динамика мирового производства и потребления никеля. Дана характеристика организационно-экономической структуры никелевой промышленности России. Обоснованы перспективы устойчивого развития никелевой промышленности в условиях шестого технологического уклада

The approaches to definition of concept "region" existing in the economic science have been systematized. The region of the Western Arctic has been singled out on the basis of localization of copper-nickel ores' fields, objects of the Arctic nickel industry on the basis of the natural and economic approach. Prospects of development of the Western Arctic nickel capacity have been proved. The leading role of the Western Arctic region in the world commodity market of nickel has been substantiated

Unexpectedly strong magnetic coupling is observed in boride insulators containing the B12 icosahedra as a structural unit. We have successfully synthesized Dy0.74B22C2N, which takes the RB22C2N-type crystal structure. The Dy phase was previously thought to not be possible to form. Spin glass-like behavior was observed with a broad peak in the zero field cooled (ZFC) magnetic susceptibility at T ∼ 44 K, while a large divergence for ZFC and field cooled (FC) curves is observed. The Curie-Weiss constant is determined to be θ=-43.9 K, and this system is indicated to have the strongest magnetic coupling ever observed for any rare earth boride insulator. Electronic structure and chemical bonding calculations were also made. Conventional mechanisms for f-electron magnetism cannot explain the strong coupling observed, which further indicates that the B12 icosahedra is functioning as a novel mediator of magnetic interaction. [ABSTRACT FROM AUTHOR]

Ga0.62(3)Sb0.38(3)Pd3, tetragonal, P4/mbm (no. 127), a = 5.5036(2) Å, c = 7.9990(3) Å, V = 242.29(3) Å3, Z = 4, Rp = 0.0168, Rwp = 0.0291, T = 295 K.

With a counterintuitive approach to crystal growth, single crystals of α-TmAlB4 were successfully grown, which were indicated from transmission electron microscopy (TEM) and x-ray diffraction (XRD) measurements and analysis to be virtually free from the ubiquitous building defects, and their properties investigated. Recent developments in rare earth aluminoboride compounds with two-dimensional boron layers have attracted interest due to the heavy fermion superconductivity in β-YbAlB4, multiple anomalies manifesting below the Néel temperatures in α-TmAlB4 attributed to intrinsic building defects, and field stable state in Tm2AlB6. The physical properties of the obtained α-TmAlB4 crystals show a striking difference from the properties of conventional α-TmAlB4 crystals containing building defects. TN = 6.8 K is revealed to be higher than the 5.8 K formerly thought, and the multiple anomalies below TN are replaced by a sharp λ-like peak in the specific heat C. The large effect of the building defects on the physical properties could be directly confirmed, and strikingly it is shown how the large peak structure in the specific heat of the high quality sample could be destroyed by the presence of a small amount (one or two percent) of building defects. [ABSTRACT FROM AUTHOR]

Eu2.88Ga8.36, orthorhombic, Immm (no. 71), a = 4.4105(3) Å, b = 4.3732(2) Å, c = 25.852(1) Å, V = 498.6 Å3, Z = 2, Rgt(F) = 0.025, wRref(F) = 0.062, T = 295 K.

EuGa2, orthorhombic, Imma (no. 74), a = 4.6459(3) Å, b = 7.6255(5) Å, c = 7.6379(3) Å, V = 270.6 Å3, Z = 4, Rgt(F) = 0.017, wRref(F) = 0.023, T = 293 K.

EuGa1.76Li0.24, orthorhombic, Imma (no. 74), a = 4.6433(4) Å, b = 7.6322(6) Å, c = 7.7341(7) Å, V = 274.1 Å3, Z = 4, Rgt(F) = 0.037, wRref(F) = 0.098, T = 293 K.

EuGa3.45Mg0.55, tetragonal, I4/mmm (no. 139), a = 4.3831(1) Å, c = 11.0632(4) Å, V = 212.5 Å3, Z = 2, Rgt(F) = 0.021, wRref(F) = 0.025, T = 295 K.

B6ErTa0.23V1.77, orthorhombic, Pbam (No. 55), a = 11.280(2) Å, b = 8.940(2) Å, c = 3.390(1) Å, V = 341.9 Å3, Z = 4, Rgt(F) = 0.034, wRobs(F) = 0.034, T = 293 K.