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All the disorder mechanisms in the 13:58 phases come together. Out of the modulated confusion rises the remarkable phase Ce12.60Cd 58.68(2)

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

Synthesis, structure, and bonding of Sc4MgxCu 15 - xGa∼7.5 (x = 0, 0.5). Two incommensurately modulated scandium substitution derivatives of cubic Mg 2Cu6Ga5

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

Cu20Sb35O44Br37 - one structure, two temperature dependencies

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

Effect of metal doping on the low-temperature structural behavior of thermoelectric β-Zn 4 Sb 3

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

Occupation waves the way you have never seen them : The orthorhombic quasicrystal approximants RE13Zn58+δ (RE = Ho, Er, Tm, and Lu)

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

Quasicrystal approximant Ho13Zn 58 + δ (δ ≈ 0.6) : An incommensurate modulated tunnel structure

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

Single-crystal growth and structure determination of misfit layer oxide [Sr2TlO3][CoO2]1.77

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 Samson phase, β-Mg2Al3, revisited

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

Low-temperature structural transitions in the phonon-glass thermoelectric material β-Zn 4 Sb 3 : Ordering of Zn interstitials and defects

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

Synthesis, crystal structure, phase relations and chemical bonding analysis of the new Nowotny chimney-ladder compound ZrBi1.62

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

Lone-pair interfaces that divide inorganic materials into ionic and covalent parts

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).

Complexity of hexagonal approximates in the RE13Zn ∼58 system (RE = Ce, Pr, Nd, Sm, Gd, Tb and Dy)

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,

Structural study of the disordered RECd6 quasicrystal approximants (RE = Tb, Ho, Er, Tm and Lu)

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 structure of onoratoite, Sb8 O11 X2 (X = Cl, Br) revisited

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

Structure and bonding properties of (Bi2Se3)m(Bi2)n stacks by first-principles density functional theory

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 crystal structure of CuSb2O3Br : Slabs from cubic Sb2O3 interspersed between puckered hexagonal CuBr-type layers

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

Inheritance of the guanidinium chloride structure in two molybdenum (II) chloride salts

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

Highly hydrated cations : Deficiency, mobility, and coordination of water in crystalline nonahydrated scandium(III), yttrium(III), and lanthanoid(III) trifluoromethanesulfonates

Trivalent lanthanide-like metal ions coordinate nine water oxygen atoms, which form a tricapped trigonal prism in a large number of crystalline hydrates. Water deficiency, randomly distributed over the capping positions, was found for the smallest metal ions in the isomorphous nonahydrated trifluoromethanesulfonates, [M-(H2O)n](CF 3SO3)3, in which M = ScIII, Lu III, YbIII, TmIII or ErIII. The hydr

Synthesis and study of Sr-substituted misfit layer sulfides

Two series of [(Ln1/3Sr2/3S)1.15] 1.15NbS2 (1.5Q/1H) and (Ln1- Sr S) 1+ NbS2 (1Q/1H) misfit layer sulfides have been synthesised and studied by X-ray powder and single crystal diffraction, EDX-analysis and magnetic measurements. For the early lanthanides (Ln = La, Ce) only the (Ln1- Sr S)1+ NbS2 (< 0.40-0.45, = 0.15-0.17) compounds were formed whereas for late lanthanides (Ln = Pr, Nd, Sm, Gd-Er,