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Synthesis and crystal structure of Ca2Ag1.83Al 0-67Ge1-50 - A solid solution with the NbCoB-type structure

The crystal structure of the new phase, Ca2Ag 1.83Al0.67Ge1.50(1) (1) was determined by single-crystal X-ray diffraction, after the compound was obtained by high temperature synthesis technique. 1 crystallizes with the NbCoB type structure in the orthorhombic space group Pmmn (no. 59) with unit cell parameters: a = 20.505(1) Â, b = 4.3807(2) Å c = 7.2211(3) Å, V= 648.65 Å3 (Z = 5). The structure o

α-Cd13-xSb10 - The devil is in the details

A detailed study of the structure of α-Cd13-xSb 10 was performed using a high quality single crystal obtained from a cadmiumrich melt. The study clearly shows that this sample is cadmium-deficient, and should more properly be labelled α-Cd13-xSb10, but whether this is true in general for this phase, or if it is an effect of the precise conditions of synthesis remains unclear. Like for the similar

Rez4Si7, first in a new MoSi2-based family of 14-electron phases

A study was conducted to investigate the geometrical and electronic connections of Re4Si7 to the rich structural chemistry of the Nowotny Chimmney Ladder phases (NCL). Re4Si7 was prepared by arc-melting a pressed pellet of Re and Si in a stoichiometric ratio, sealing the resulting globule in an excavating quartz tube, and annealing the sample in a muffle furnace. It was found that NCLs were interm

To what extent does the zintl-klemm formalism work? The Eu(Zn 1 - X Ge X ) 2 series

The series of ternary polar intermetalllcs Eu(Zn 1-x Ge x ) 2 0≤x≤ 1) has been investigated and characterized by powder and single-crystal X-ray diffraction as well as physical property measurements. For 0.50(2) 0.75, respectively, orthorhombic KHg 2 -type and trigonal EuGe 2 -type phases occur as a second phase in mixtures with an AIB 2 -type phase. Diffraction of the x= 0.75(2) sample sh

Zn 5Sb 4In 2-δ - A ternary derivative of thermoelectric zinc antimonides

Zn 5Sb 4ln 2-δ (δ = 0.15(3)) was synthesized in the form of millimeter-sized crystals from reaction mixtures containing excess zinc. The ternary intermetallie compound is temperature polymorphic, and at room temperature it crystallizes with a new structure type in the orthorhombic space group Pbcn, where a = 7.1619(2), b= 17.1562(4), c=8.6887(4) Å, V = 1067.6(1) Å 3, and Z = 4. The structure featu

Cd13-xinySb10 (x≈ 2.7, y≈1.5) : An interstitial-free variant of thermoelectric ß-Zn 4Sb3

Cd13-x;In7Sb10 (x≈2.7, Y≈ 1.5) was synthesized in the form of millsized crystals from reaction mixtures containing excess cadmium. The intermetallic compound crystallizes in the rhombohedral space group R3m with α = 12.9704(4), c= 12.9443(5) Å, V= 1886.0(1) Å3, Z=3 and is isostructural to thermoelectric ß-Zn 4Sb3 and ßCd4Sb3. However, in contrast to these last two compounds Cd13-xInySb 10 is free

Modulations in the onoratoite system

The iodide form of the mineral onoratoite was synthesized, and like the Cl and Br based analogues, it displays super structure ordering, but for the iodide, the super structure is clearly incommensurate. Due to the poor quality of crystals attainable, the structure was solved by converting the solution of the Cl analogue to a super space formalism, and then using the structural elements from this

Incommensurate stistaite - Order made to order

The structure of stistaite -SbSn, was investigated by single crystal X-ray diffraction and EDX to yield a simple relation between the modulated structure and the composition. Stistaite is found to be ineommensurately ordered over the entire stability region.

Structural model for octagonal quasicrystals derived from octagonal symmetry elements arising in β-Mn crystallization of a simple monatomic liquid

While performing molecular-dynamics simulations of a simple monatomic liquid, we observed the crystallization of a material displaying octagonal symmetry in its simulated diffraction pattern. Inspection of the atomic arrangements in the crystallization product reveals large grains of the β-Mn structure aligned along a common fourfold axis, with 45° rotations between neighboring grains. These 45° r

The structure of Cu6Sn5-xSbx - large effects of subtle Doping

Small amounts of antimony shifts the thermal stability range of ht-Cu 6Sn5. To make this phase stable at room temperature, and easily accessible by prolonged annealing, a model previously suggested for the ht-phase is shown to be entirely correct in this single crystal study.

Helical chains of [MO5Cl] octahedra - Three compounds in the new family AEM2Te3O8Cl2 (AE = Ca, Sr and M = Co, Ni)

The compounds CaCo2Te3O8Cl2, SrCo2Te3O8Cl2 and SrNi2Te3O8Cl2 were synthesized via solid-gas reactions and investigated using single-crystal X-ray diffraction. While the compound CaCo2Te3O8Cl2 formed large enough single crystals to allow for a detailed structural analysis, crystals of the Sr-containing compounds yielded evidence that they are isostructural. CaCo2Te3O8Cl2 crystallizes in the monocli

Two for the price of one - Resolvable polymorphism in a 'single crystal' of α- and β-Sb3O4I

The title compound forms as biphasic single crystals containing the α- and β-polymorphs. The structure of both polymorphs was solved and refined from single crystal X-ray data in a simultaneous refinement. The structures consist of rods of composition Sb3O4 separated by isolated iodine ions. The two phases differ only in the next nearest neighbour arrangement. The orthorhombic α-phase crystallizes

Metastable Cd4Sb3 : A complex structured intermetallic compound with semiconductor properties

The metastable binary intermetallic compound Cd4Sb3 was obtained as polycrystalline ingot by quenching stoichiometric Cd-Sb melts and as mm-sized crystals by employing Bi or Sn fluxes. The compound crystallizes in the monoclinic space group Pn with a = 11.4975(5) Å, b = 26.126(1) Å, c = 26.122(1) Å, β = 100.77(1)°, and V = 7708.2(5) A,̊3. The actual formula unit of Cd4Sb3 is Cd13Sb10 and the unit

A new compound in the Cu-In system - The synthesis and structure of Cu 10In7

A new binary phase, Cu10In7, was found during the investigation of the η?-phase field in the Cu-In system. Single crystals of Cu10In7 were grown from a melt under an inert atmosphere. The compound crystallizes in the monoclinic space group C2/m with cell parameters a = 13.8453(2)A ° , b = 11.8462(1)A ° , c = 6.7388(1)A ° and ?β = 91.063(1). The structure is based on a unit of face-sharing octahedr

Anomalous low-temperature behavior of the Co dimers in the oxo-halide CoSb2O3Br2

We report the synthesis, crystal structure determination, magnetic and low-temperature structural properties of a new cobalt antimony oxo-bromide. CoSb2O3Br2 crystallizes in the triclinic crystal system, space group P-1, with the following lattice parameters: a = 5.306(3) Å, b = 7.812(4) Å, c = 8.0626(10) Å, α = 88.54(3)°, β= 82.17(3)°, γ = 80.32(4)°, and Z = 2. The crystal structure was solved fr

Single-crystal X-ray study of Ba2Cu2Te 4O11Br2 and its incommensurately modulated superstructure companion

Compounds containing lone-pair elements such as TeIV are very interesting from the structural point of view, as the lone-pair nonbonding regions create low-dimensional geometrical arrangements. We have synthesized two new compounds with these features - Ba2Cu2Te 4O11Br2 (I) and Ba2Cu 2Te4O11-δ(OH)2δBr 2 (II, δ ≈ 0.57) - as members of the AE-M-Te-O-X (AE = alkaline-earth metal, M = transition metal

Origins of superstructure ordering and incommensurability in stuffed CoSn-type phases

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

Vacancy-ordering effects in AlB2-type ErGe2 - X (0.4 < x ≤ 0.5)

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

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