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The CoSn structure type contains large interstitial void spaces that frequently host electropositive guest atoms, such as rare earth elements. In this stuffing process, an intriguing ordering occurs between the neighboring void spaces leading to a family of long-period superstructures comprising intergrowths of the ScFe6Ge6 and ScFe6Ga 6 structure types. This superstucture ordering culminates in i
In the Er-Ge system, the compostion range ErGe2 to Er2Ge3 has been investigated. Eight samples were produced by arc melting of the elements, and analyzed using X-ray powder diffraction. Nine crystal structures were found to be present in the samples. The structures are described as a homologous series and presented within the superspace formalism using the superspace group X2/m(α0γ)0s, X represent
The compound Ce12.60Cd58.68(2) is a metrically commensurate representative of the incommensurately modulated phase Ce 13Cd57+δ. It is most likely a lock-in phase. The structure, which was solved using seeding of the modulation from those positions most affected as well as direct solution by charge flipping, represents a rare case of ordering in a family of structures where disorder is the rule. Th
The substitution of scandium for magnesium in Mg2Cu 6Ga5 (Mg2Zn11-type) yields an irrational superstructure phase that includes the refined compositions, Sc 4Mg0.50(2)Cu14.50(2)Ga7.61(2) and Sc4Cu14.76(2)Ga7.51(2). These crystallize in Cmmm, a = ∼8.31 Å, b = ∼21.72 Å, c = ∼8.30 Å. The structures feature Sc2 dimers, Cu6 octahedra, a 3D CuGa (Cu12Ga2) framework, and arachno gallium-centered Cu 4Ga6
The structure of the new compound Cu20Sb35O44Br37 was examined at different temperatures and compared to the previously prepared structural analogue Cu20Sb35O44Cl37. The structure comprises two major units; isolated [Sb35O44Br5]12+ clusters shaped as typical sodalite building blocks (β-cages) and one-dimensional continuous CuBr chains of edge sharing super-tetrahedra. The covalent and ionic buildi
The low-temperature structural phase transitions of Bi, Pb, In and Sn-doped samples of thermoelectric Zn 4 Sb 3 have been characterized on crystals grown from molten metal fluxes, using electrical resistance and single crystal X-ray diffraction measurements. Room temperature stable, disordered, β-Zn 4 Sb 3 undergoes two phase transitions at 254 and 235 K to the consecutively higher ordered phases
A series of binary quasicrystal approximants RE13Zn 58+δ (RE = Ho, Er, Tm, and Lu) have been prepared, and structural studies were performed by means of single-crystal X-ray diffraction. All four compounds crystallize in the orthorhombic system, but while the Ho-containing compound crystallizes in space group Pcmn, the rest of the compounds crystallize in Pc21n. This work is a continuation of the
In a systematic study of the binary quasicrystal approximants RE13Zn58 (RE = rare earth elements) system, single crystals of Ho13Zn58 + have been prepared. It is unique among family members of the RE13Zn58 system in that it shows a modulated superstructure ordering. Satellite reflections observed in single crystal X-ray diffraction pattern indicate the presence of a one-dimensional lattice distort
We have synthesized single crystals of the misfit layer cobaltate [Sr2TlO3][CoO2]1.77 and determined its crystal structure by the means of X-ray single-crystal diffraction (XRSD) and transmission electron microscopy. The synthesis took place by spontaneous crystallization from an oxide melt at high gaseous pressure. The structure is described by two monoclinic subsystems, which share the unit cell
The Al-Mg phase diagram has been reinvestigated in the vicinity of the stability range of the Samson phase, β-Mg2Al3 (cF1168). For the composition Mg38.5Al61.5, this cubic phase, space group Fd3̄m (no 227), a = 28.242(1) Å, V = 22526(2) Å3, undergoes at 214°C a first-order phase transition to rhombohedral β′-Mg2Al3, (hR293), a = 19.968(1) Å, c = 48.9114(8) Å, V = 16889(2) Å3, (i.e. 22519 Å3 for th
Using infrared reflection spectroscopy the authors show that the phase transitions from disordered high temperature Β- Zn4 Sb3 into the increasingly higher ordered and complex structured low-temperature phases α and α′ are accompanied by a significant increase in the free charge carrier density and a concomitant increase of the effective scattering rate.
The low-temperature phase transitions of thermoelectric Zr 4 Sb 3 have been characterized using singlecrystal X-ray diffraction, electrical resistance, and thermal conductivity measurements. Room-temperature stable, disordered β-Zn 4 Sb 3 undergoes a phase transition at 254 K to ordered α-n 4 Sb 3 , which has an ideal composition Zn 4 Sb 10 . Below 235 K, a second low-temperature phase (α′-Zn
ZrBi1.62 is a new compound crystallising with an incommensurate Nowotny chimney-ladder structure, which was refined from single crystal X-ray diffraction data using a four-dimensional formalism. The tetragonal unit cell has the lattice parameters a = 6.958 (7) Å, c = 3.460 (3) Å and q = (0 0 0.382). The symmetry is described by the superspace group pair W:P4/nnc:q-1q1-P:I41/amd:1-1ss. The full pha
The lone (ar)ranger: The structure of Cu20Sb35O 44Cl37 is divided up into two parts: ionically bonded Cu+-Cl- supertetrahedra (green) and covalently bonded clusters that resemble zeolite β cages. The Sb3+ ions (gray) lie at the vertices of the cages, while their lone pairs of electrons form surfaces that separate the covalent and ionic parts. (Figure Presented).
For the RE13Zn58 quasicrystal approximants (RE = Ce, Pr, Nd, Sm, Gd, Tb, Dy), single crystals were prepared from the elements and their structures were refined from single-crystal X-ray diffraction data. They are derived from the Gd13Cd58 type structure and crystallize in the space group P63/mmc or its subgroups. The crystal structures of Ce and Pr compounds are identical to that of the archetype,
The crystal structures of approximants RECd6 (RE = Tb, Ho, Er, Tm and Lu) have been refined from single crystal X-ray diffraction data. This work is a continuation of a previous study of MCdg approximants [1] in which the different types of disorder of the central Cd4 tetrahedra located in the dodecahedral cavities were examined. The structures of the title compounds are all similar to GdCd6 and d
The crystal structure of Sb8O11Cl2 (onoratoite) is redetermined in the triclinic space group P-1. The crystal structure was previously described by a partially disordered model in the monoclinic space group C 2 / m containing some partially occupied oxygen atoms. The new structural model features exclusively atomic positions that are fully occupied. The crystal structure was solved from single cry
We have investigated crystal structure, chemical bonding, and electronic properties of the compounds Bi2Se3, BiSe, Bi4Se3, and Bi2Se by first-principles calculations within the density functional theory. The compounds are members of a general series of stacks (Bi2Se3)m(Bi2)n composed of five-layer blocks Se-Bi-Se-Bi-Se and two-layer blocks Bi-Bi. Both types of blocks can be considered as closed-sh
The new compound CuSb2O3Br crystallize in the monoclinic space group Cc. The unit cell parameters are a=7.9189(15)Å, b=13.7105(10)Å, c=19.048(2)Å, β=90°, Z=16. The crystal structure is solved from single crystal data, R=0.0490. The compound show a layered structure with slabs from cubic Sb2O3 interspersed in between puckered layers of CuBr. The Sb(III) atoms have tetrahedral [SbO3E] coordination w
Depending on the proticity of the solvent, two different salts may be crystallized from the combination of solutions of guanidinium chloride, C(NH2)3Cl, and the acidic hydrate of molybdenum dichloride, [(Mo6Cl8)Cl6](H20 O9). From aprotic solvents such as dimethyl sulfoxide (DMSO) or formamide (FA), compound I, [(Mo6Cl8) Cl6]Cl6(C(NH2)3)8, crystallizes, while from protic solvents such as ethanol or
