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La12Mg46LiMn, cubic, Fm3‾m $Fm\overline{3}m$ (no 225), a = 14.7119(3) Å, V = 3184.24(19) Å3, Z = 2, R gt(F) = 0.0330, wR ref(F 2) = 0.0601, T = 293(2) K.

La3.65Mg30Sb1.07, hexagonal, P63/mmc (no. 194), a = 10.3895(2) Å, c = 10.2547(3) Å, V = 958.61(5) Å3, Z = 1, R gt(F) = 0.0166, wR ref(F 2) = 0.0429, T = 293(2) K.

The ternary germanide Mg5.57Ni16Ge7.43 (cubic, space group Fmm, cF116) belongs to the structural family based on the Th6Mn23‐type. The Ge1 and Ge2 atoms fully occupy the 4a (mm symmetry) and 24d (m.mm) sites, respectively. The Ni1 and Ni2 atoms both fully occupy two 32f sites (.3m symmetry). The Mg/Ge statistical mixture occupies the 24e site with 4m.m symmetry. The structure of the title compound contains a three‐core‐shell cluster. At (0,0,0), there is a Ge1 atom which is surrounded by eight Ni atoms at the vertices of a cube and consequently six Mg atoms at the vertices of an octahedron. These surrounded eight Ni and six Mg atoms form a [Ge1Ni8(Mg/Ge)6] rhombic dodecahedron with a coordination number of 14. The [GeNi8(Mg/Ge)6] rhombic dodecahedron is encapsulated within the [Ni24] rhombicuboctahedron, which is again encapsulated within an [Ni32(Mg/Ge)24] pentacontatetrahedron; thus, the three‐core‐shell cluster [GeNi8(Mg/Ge)6@Ni24@Ni32(Mg/Ge)24] results. The pentacontatetrahedron is a new representative of Pavlyuk's polyhedra group based on pentagonal, tetragonal and trigonal faces. The dominance of the metallic type of bonding between atoms in the Mg5.57Ni16Ge7.43 structure is confirmed by the results of the electronic structure calculations. The hydrogen sorption capacity of this intermetallic at 570 K reaches 0.70 wt% H2. [ABSTRACT FROM AUTHOR]

The ternary magnesium/lithium boride, MgxLi3 - xB48 - y (x = 1.11, y = 0.40, idealized formula MgLi2B48), crystallizes as its own structure type in P43212, which is closely related to the structural family comprising α-AlB12, Be0.7Al1.1B22 and tetragonal β-boron. The asymmetric unit of title structure contains two statistical mixtures Mg/Li in Wyckoff sites 8b with relative occupancies Mg:Li = 0.495 (9):0.505 (9) and 4a with Mg:Li = 0.097 (8):0.903 (8). The boron atoms occupy 23 8b sites and two 4a sites. One of the latter sites has a partial occupancy factor of 0.61 (2). Both unique Mg/Li atoms adopt a twelvefold coordination environment in the form of truncated tetrahedra (Laves polyhedra). These polyhedra are connected by triangular faces to four [B12] icosahedra. The boron atoms exhibit four kinds of polyhedra, namely pentagonal pyramid (coordination number CN = 6), distorted tetragonal pyramid (CN = 5), bicapped hexagon (CN = 8) and gyrobifastigium (CN = 8). At the gas hydrogenation of MgLi2B48 alloy, formation of the eutectic composite hydride LiBH4+Mg(BH4)2 and amorphous boron is observed. In the temperature range 543-623 K, the hydride eutectics decompose, forming MgH2, LiH, MgB4, B and H2. [ABSTRACT FROM AUTHOR]

Fully biodegradable foils were prepared from potato starch, egg albumin, and either stearic or oleic acid. Foils prepared with oleic acid have higher tensile strength, relative elongation, thermal stability, and a more uniform macrostructure. Foils produced with stearic acid were characterized by a higher index of crystallinity than foils made with oleic acid. Functional properties of the foils can be modulated involving a sequence of blending of their components. The simultaneous blending of starch (10 weight parts of 5% aq. gel), albumin (1 weight part of liquid composed of 1 g of albumin in 7 mL of water), and stearic acid (5 weight parts of powder) provided the foil with the highest tensile strength (64.91 MPa/mm). Independently of the method of preparation, foils were white with a greenish-yellow shade. Analysis of the ATR-FTIR spectra showed that the macrostructure of the foils is built involving interactions between all three components. [ABSTRACT FROM AUTHOR]

This paper concentrates on electrochemical properties of groups of multi-walled carbon nanotubes (MWCNT) functionalized with substituents containing a stereogenic heteroatom bonded covalently to the surface of the carbon nanotube. This system was tested in Swagelok-type cells. The cells comprised a system (functionalized CNT with salts containing S and P atoms) with a working electrode, microfiber separators soaked with electrolyte solution, and a lithium foil counter/reference (commercial LiCoO2) electrode. The electrolyte solution was 1 M LiPF6 in propylene carbonate. Using standard techniques (cyclic voltammetry/chronopotentiometry), galvanostatic cycling was performed on the cells at room temperature with a CH Instruments Model 600E potentiostat/galvanostat electrochemical measurements. Methods of functionalization CNT were compared in terms of the electrochemical properties of the studied systems. In all systems, the process of charge/discharge was observed.

Crystal structures of MgCoGa, Mg0.74CoGa0.52 and Mg0.49CoGa0.15 phases from the Mg–Co–Ga system were investigated using single‐crystal diffraction. These structures belong to the family of so‐called Laves phases. Hexagonal MgCoGa crystallizes as a disordered phase within the MgZn2 structure type. The orthorhombic structure of Mg0.74CoGa0.52 is a distortion variant of MgZn2 and URe2 structure type, and the structural relation is demonstrated in terms of a Bärnighausen formalism group–subgroup transformation scheme. The structure of trigonal phase Mg0.49CoGa0.15 is strongly disordered, as is shown by the presence of adjacent atomic sites which cannot be occupied simultaneously. In Mg0.49CoGa0.15, two subcells (A and B) were obtained in a ratio of 9:1. Subcell A is closely related to MgZn2‐type. [ABSTRACT FROM AUTHOR]

La12Mg46LiMn, cubic, F m 3 ‾ m (no 225), a = 14.7119(3) Å, V = 3184.24(19) Å3, Z = 2, Rgt(F) = 0.0330, wRref(F2) = 0.0601, T = 293(2) K. [ABSTRACT FROM AUTHOR]

The ternary Tb2–xNdxZn17–yNiy (x = 0.5, y = 4.83) disordered phase belongs to the structural family based on the rhombohedral Th2Zn17 structure type. The structure is maximally disordered since all the sites are occupied by statistical mixtures of atoms. The Tb/Nd mixture of atoms occupies the 6c site (site symmetry 3m). The statistical mixtures Ni/Zn consisting of more Ni atoms are located in the 6c and 9d (symmetry.2/m) sites. In the following 18f (site symmetry.2) and 18h (site symmetry.m) sites are located Zn/Ni statistical mixtures which consist of more Zn atoms. Zn/Ni atoms form three‐dimensional networks with hexagonal channels that fill statistical mixtures of Tb/Nd and Ni/Zn. The Tb2–xNdxZn17–yNiy compound belongs to the family of intermetallic phases capable of absorbing hydrogen. In the structure, there are three types of voids, namely, 9e (site symmetry.2/m), 3b (site symmetry m) and 36i (site symmetry 1), in which hydrogen can be inserted, and the maximum total absorption capacity can reach 1.21 wt% H2. Electrochemical hydrogenation shows that the phase absorbs 1.03% of H2, which indicates partial filling of the voids with H atoms. [ABSTRACT FROM AUTHOR]

La5Zn2−xPb1 + x (x = 0.20–0.32), tetragonal, I4/mcm (no. 140), a = 8.1673(12) Å, c = 15.367(3) Å, V = 1025.1(3) Å3, Z = 4, Rgt(F) = 0.0261, wRref(F2) = 0.0441, T = 293 K.

Three new iridium aluminum intermetallics CaAl4Ir2, SrAl4Ir2, and EuAl4Ir2 were synthesized from the elements using silica or tantalum ampoules. They crystallize in the tetragonal crystal system with space group P4/ncc and lattice parameters of a = 782.20(1) and c = 779.14(2) pm for CaAl4Ir2, a = 797.62(1) and c = 772.75(2) pm for SrAl4Ir2, and finally a = 791.78(5) and c = 773.31(5) pm for EuAl4Ir2. All compounds crystallize isostructurally and adopt a new structure type that can be derived from the KAu4In2 type structure. To compare the structures from a crystallographic point of view, a group–subgroup relation between KAu4In2 and EuAl4Ir2 as well as KAu4In2 and KAu4Sn2 have been established using the Bärnighausen formalism. Finally, quantum-chemical calculations have been conducted, showing that in all three title compounds, a polyanionic [Al4Ir2]δ– network exists with significant (polar) bonding interactions, while the respective Caδ+, Srδ+, and Euδ+ cations are located in octagonal channels. [ABSTRACT FROM AUTHOR]

YNiIn and YCuIn form complete solid solutions YNiIn1−xAlx and YCuIn1−xAlx, which were characterized on the basis of X-ray powder diffraction. The ZrNiAl type crystal structures (space groups P 6 ‾ 2 m ) of YNiAl (a = 0.70386(9), c = 0.38327(4) nm, wR2 = 0.0424), YNiIn0.77Al0.23 (a = 0.73895(9), c = 0.37707(4) nm, wR2 = 0.0498) and YCuIn0.63Al0.37 (a = 0.73404(7), c = 0.39045(4) nm, wR2 = 0.0314) were refined from the single crystal X-ray diffraction data. Exemplarily the electronic structure of YNiAl was studied, manifesting substantial Ni–Al bonding within the three-dimensional [NiAl] substructure. Comparison of YNiAl with isotypic YNiIn shows stronger Ni–Al bonding as compared to Ni–In. Magnetic susceptibility measurements of YNiIn1−xAlx (x = 0.1, 0.2, 0.7 and 0.9), YNiIn and YNiAl in the temperature range 3–300 K indicated Pauli paramagnetic behaviour with molar magnetic susceptibility of about 0.15–0.22 × 10−3 emu/mol. [ABSTRACT FROM AUTHOR]

The Laves phase Mg2MnGa3 was synthesized from the elements by arc-melting and subsequent annealing in a silica ampoule at T = 670 K. The structure of Mg2MnGa3 was refined from single-crystal X-ray diffractometer data: URe2 type, Cmcm, a = 543.24(1), b = 869.59(3), c = 858.58(2) pm, wR2 = 0.0556, 273 F2 values and 24 variables. The manganese and gallium atoms form a three-dimensional network of corner- and face-sharing MnGa3 tetrahedra that derive as a ternary ordering variant from the hexagonal Laves phase MgZn2. The structures of the distortion and coloring variants, i.e., MgZn2, URe2, Mg2Cu3Si and Mg2MnGa3 are discussed on the basis of a Bärnighausen tree. The electronic structure calculation data indicate that in addition to the metallic type of bonding an additional covalent interaction appears between the Ga–Ga and Mn–Ga atoms. [ABSTRACT FROM AUTHOR]

The isothermal section at 473 K of the Mg-Ni-Ga system in the entire composition regime and structural characterizations of the observed ternary phases are reported. The MgNi1+xGa1-x (x = 0.25), MgNiGa, Mg2NiGa3, Mg9-xNi6Ga14-y (x = 0.32, y = 0.84), Mg3Ni2Ga, and MgNi2Ga5 structures were solved and refined from X-ray single crystal diffraction data. MgNi1+xGa1-x (x = 0.25, Fd-3 m, a = 7.0781(2) Å) and MgNiGa (P63/mmc, a = 5.0781(3) Å, c = 8.194(1) Å) crystallize in the Laves phase MgCu2 and MgZn2 structure types, respectively. Mg2NiGa3 (Cmcm, a = 5.415(1) Å, b = 8.651(1) Å, c = 8.562(2) Å, Mg2MnGa3-type) represents the orthorhombic derivative of Laves phases. Mg9-xNi6Ga14-y (x = 0.32, y = 0.84, Fd-3 m, a = 19.8621(6) Å) is isostructural with Mg35Cu24Ga53. MgNi2Ga5 (Pnnm, a = 6.2704(1) Å b = 6.6902(1) Å c = 6.0794(1) Å) crystallizes in the MgCo2Ga5-type structure which is derived from tetragonal CoGa3-type. The crystal chemistry of these structures is compared and discussed. The hydrogenation properties of the MgNi1+xGa1-x (x = 0.25), MgNiGa, and Mg2NiGa3 Laves phases were studied. MgNi1.25Ga0.75 absorbs up to 2.20 wt.% H2, MgNiGa absorbs up to 1.78 wt.% H2, and Mg2NiGa3 absorbs up to 1.66 wt.% H2. [ABSTRACT FROM AUTHOR]

The new ternary gallide MgMn4Ga18 (magnesium tetramanganese octadecagallium) was synthesized and its crystal structure determined by means of single‐crystal X‐ray diffraction. The MgMn4Ga18 structure can be described as that of a three core–shell cluster compound. The Mg atoms are surrounded by 16 adjacent Ga atoms, [MgGa16], and the respective coordination polyhedron is an octadecahedron. This [MgGa16] octadecahedron is encapsulated inside a [Ga32] icohexahedron, which is in turn encapsulated inside a [Ga40] pentacontaoctahedron. As a result, a three core–shell cluster, [MgGa16@Ga32@Ga40], is identified. Electronic structure calculations were performed by means of the TB‐LMTO‐ASA program and additionally confirm the existence of the core–shell packing of the clusters. [ABSTRACT FROM AUTHOR]