Structural Reinvestigation of Alkali Hexatitanate

2011 ◽  
Vol 170 ◽  
pp. 208-212
Author(s):  
Kunimitsu Kataoka ◽  
Norihito Kijima ◽  
Hiroshi Hayakawa ◽  
Junji Akimoto
Keyword(s):  
Ion Exchange ◽  
Single Crystal ◽  
Molten Salt ◽  
Type Structure ◽  
Exchange Method ◽  
Space Group ◽  
X Ray ◽  
Structure Space ◽  
Li Ion ◽  
Ion Exchange Method

Na1.614Li0.386Ti6O13 Single crystal was synthesized by a Li+ ion-exchange method from Na2Ti6O13 single crystal in a molten salt of LiNO3. The obtained Na1.614Li0.386Ti6O13 single-crystal is colorless and has the shape of a rod. Na1.614Li0.386Ti6O13 crystallizes in the monoclinic tunnel type structure, space group C2/m, and lattice parameters a = 15.144(2) Å, b = 3.7492(5) Å, c = 9.162(2) Å and β = 99.0131(9)º. The structure was determined by a single-crystal X-ray study and refined to the conventional values of R = 0.0247 and wR = 0.0451 for 969 independent observed reflections.

CaPtIn4 – an intergrowth variant of CaPtIn2 and indium slabs

2019 ◽  
Vol 74 (9) ◽  
pp. 693-698 ◽  
Author(s):  
Birgit Heying ◽  
Jutta Kösters ◽  
Rainer Pöttgen
Keyword(s):  
Intermetallic Compound ◽  
Single Crystal ◽  
Peritectic Reaction ◽  
Three Dimensional ◽  
Type Structure ◽  
Space Group ◽  
X Ray ◽  
Structure Space ◽  
Indium Metal

AbstractThe indium-rich intermetallic compound CaPtIn4 is formed in a peritectic reaction of CaPtIn2 and indium metal at T = 670 K (14 days annealing). CaPtIn4 crystallizes with the YNiAl4-type structure, space group Cmcm, which was refined from single crystal X-ray diffractometer data: a = 446.3(5), b = 1659.50(18), c = 756.8(8) pm, wR2 = 0.0646, 640 F2 values and 24 variables. Geometrically one can describe the CaPtIn4 structure as an intergrowth variant of CaPtIn2 (MgCuAl2 type) and indium slabs. The three-dimensional [PtIn4] polyanionic network shows short Pt–In distances of 269–280 pm and a broader range of In–In distances (304–378 pm) within substantially distorted In@In8 cubes.

Rare Earth-rich Cadmium Compounds RE4TCd (T = Ni, Pd, Ir, Pt)

2008 ◽  
Vol 63 (9) ◽  
pp. 1127-1130 ◽  
Author(s):  
Falko M. Schappacher ◽  
Ute Ch. Rodewald ◽  
Rainer Pöttgen
Keyword(s):  
Rare Earth ◽  
Transition Metal ◽  
Single Crystal ◽  
Intermetallic Compounds ◽  
Three Dimensional ◽  
Type Structure ◽  
Space Group ◽  
X Ray ◽  
Structure Space ◽  
Cadmium Compounds

New intermetallic compounds RE4TCd (RE = Y, La-Nd, Sm, Gd-Tm, Lu; T = Ni, Pd, Ir, Pt) were synthesized by melting of the elements in sealed tantalum tubes in a highfrequency furnace. They crystallize with the Gd4RhIn-type structure, space group F 4̄3m, Z = 16. The four gadolinium compounds were characterized by single crystal X-ray diffractometer data: a = 1361.7(1) pm, wR2 = 0.062, 456 F2 values, 19 variables for Gd4NiCd; a = 1382.1(2) pm, wR2 = 0.077, 451 F2 values, 19 variables for Gd4PdCd; a = 1363.6(2) pm, wR2 = 0.045, 494 F2 values, 19 variables for Gd4IrCd; a = 1379.0(1) pm, wR2 = 0.045, 448 F2 values, 19 variables for Gd4PtCd. The rare earth atoms build up transition metal-centered trigonal prisms which are condensed via common corners and edges, leading to three-dimensional adamantane-related networks. The cadmium atoms form Cd4 tetrahedra which fill voids left in the prisms’ network.

Indides RE3T2In4 (RE = Y, Gd–Tm, Lu; T = Ni, Ru, Rh) with a ZrNiAl superstructure

2016 ◽  
Vol 71 (12) ◽  
pp. 1261-1267 ◽  
Author(s):  
Birgit Heying ◽  
Oliver Niehaus ◽  
Ute Ch. Rodewald ◽  
Rainer Pöttgen
Keyword(s):  
Rare Earth ◽  
Transition Metal ◽  
Transition Metals ◽  
Single Crystal ◽  
Symmetry Reduction ◽  
Type Structure ◽  
Crystal Chemical ◽  
Space Group ◽  
X Ray ◽  
Structure Space

AbstractThree series of rare earth-transition metal-indides RE3T2In4 (RE=Y, Gd–Tm, Lu; T=Ni, Ru, Rh) were synthesized from arc-melted RE3T2 precursor compounds and indium tear shot in sealed niobium ampoules using different annealing sequences. The new indides crystallize with the hexagonal Lu3Co2In4-type structure, space group P6̅. All samples were characterized on the basis of Guinier powder patterns and six structures were refined from single crystal X-ray diffractometer data. The RE3T2In4 structures are derived from the ZrNiAl type through RE/In ordering, paralleled by a symmetry reduction from P6̅2m to P6̅. This induces twinning for some of the investigated crystals. The main crystal chemical motifs of the RE3T2In4 structures are trigonal prisms of rare earth, respectively indium atoms that are filled by the transition metals.

La5Ir1.73In4.27 with Lu5Ni2In4-type structure

2020 ◽  
Vol 75 (6-7) ◽  
pp. 709-713
Author(s):  
Nataliya Dominyuk ◽  
Vasyl’ I. Zaremba ◽  
Rainer Pöttgen
Keyword(s):  
Single Crystal ◽  
Single Crystals ◽  
Small Degree ◽  
Type Structure ◽  
Muffle Furnace ◽  
Space Group ◽  
One Dimensional ◽  
X Ray ◽  
Structure Space ◽  
Arc Melting

AbstractSingle crystals of La5Ir1.73In4.27 were grown from a sample of the starting composition 47La: 17Ir: 36 In by arc-melting, followed by a long annealing sequence in a muffle furnace. La5Ir1.73In4.27 crystallizes with the Lu5Ni2In4-type structure, space group Pbam, which was refined from single-crystal X-ray diffractometer data: a = 834.0(2), b = 1862.2(4), c = 385.31(8) pm, wR2 = 0.0278, 1165 F2 values and 37 variables. The 4h iridium site shows a small degree of Ir/In mixing. Geometrically one can describe the La5Ir1.73In4.27 structure as a simple 4:1 intergrowth variant of CsCl and AlB2-related slabs. The iridium and indium atoms form a one-dimensional meandering [Ir1.73In4.27]δ– polyanion (292 pm Ir–In and 327 pm In–In) which is embedded in a lanthanum matrix.

Quaternary Phosphide Oxides Pr3Cu4P4O2–x and Sm3Cu4P4O2–x with Ordered Zr3Cu4Si6-Type Structure

2002 ◽  
Vol 57 (2) ◽  
pp. 165-170 ◽  
Author(s):  
Joachim W. Kaiser ◽  
Wolfgang Jeitschko
Keyword(s):  
Single Crystal ◽  
Chemical Bonding ◽  
Empirical Formula ◽  
Type Structure ◽  
Formula Unit ◽  
Variable Parameters ◽  
Space Group ◽  
X Ray ◽  
Structure Space ◽  
Structure Factors

The compounds Ln3Cu4P4O2-χ (Ln = Pr, Sm) were prepared by annealing the elemental components in a NaCl/KCl flux. They crystallize with an ordered Zr3Cu4Si6-type structure (space group I4/mmm, Z = 2), which was refined from single-crystal X-ray data for both compounds; Pr3Cu4P4O2-χ: a = 397.8(1), c = 2658.7(3) pm, R = 0.046 for 235 structure factors and 19 variable parameters; Sm3Cu4P4O2-χ: a = 392.8(1), c = 2643.6(3) pm, R = 0.057 for 145 F values and 19 variables. The refinements showed partial occupancy for the oxygen positions resulting in approximately 1.5 oxygen atoms per formula unit. Half of the phosphorus atoms form pairs with typical two-electron bond distances of 222.8(4) and 221.7(8) pm, respectively. Using oxidation numbers chemical bonding in these phosphide oxides can be rationalized with the formula (Ln+3)3(Cu+1)4(P-P)-4(P-3)2(O-2)1.5. Hence, the empirical formula may also be doubled (Ln6Cu8P8O3), and the compounds are expected to be semiconducting.

MgCuAl2-type Intermetallics REPdCd2(RE = Ce, Pr, Nd, Sm)

2012 ◽  
Vol 67 (11) ◽  
pp. 1221-1224 ◽  
Author(s):  
Michael Johnscher ◽  
Rainer Pöttgen
Keyword(s):  
Single Crystal ◽  
Intermetallic Compounds ◽  
High Frequency ◽  
Three Dimensional ◽  
Type Structure ◽  
Subsequent Annealing ◽  
Space Group ◽  
X Ray ◽  
Structure Space ◽  
Structure Factors

The cadmium-rich intermetallic compounds REPdCd2 (RE=Ce, Pr, Nd, Sm) were obtained by high-frequency melting of the elements in sealed niobium ampoules and subsequent annealing in muffle furnaces. The REPdCd2 phases crystallize with the orthorhombic MgCuAl2-type structure, space group Cmcm. The structure of NdPdCd2 was refined from single-crystal X-ray diffractometer data: a=421.9(3), b=995.4(7), c=834.5(6) pm, wR=0.0286, 451 structure factors, 16 variables. The palladium and cadmium atoms build up a three-dimensional [PdCd2] network (281 - 283 pm Pd-Cd; 298 - 335 pm Cd-Cd) in which the neodymium atoms fill cavities. They are connected to the [PdCd2] network via shorter Nd-Pd bonds of 286 pm.

Crystal structure of LnCuSn (Ln = Nd, Sm, Gd)

1998 ◽  
Vol 213 (10) ◽  
Author(s):  
J. V. Pacheco ◽  
K. Yvon ◽  
E. Gratz
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Type Structure ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Structure Space

AbstractThe title compounds were reinvestigated by single crystal X-ray diffraction. They crystallize with the ordered NdPtSb type structure (space group

Gold-Tin Ordering in SrAu2Sn2

2014 ◽  
Vol 69 (7) ◽  
pp. 767-774 ◽  
Author(s):  
Christian Schwickert ◽  
Birgit Gerke ◽  
Rainer Pöttgen
Keyword(s):  
Single Crystal ◽  
Coordination Number ◽  
Solid Solutions ◽  
High Frequency ◽  
Spectroscopic Data ◽  
Type Structure ◽  
Temperature Dependent ◽  
Space Group ◽  
X Ray ◽  
Structure Space

Samples of the solid solutions SrAuxSn4−x (1:7 ≤ x ≤ 2:2) were obtained by high-frequency melting of the elements in sealed niobium ampoules. Powder and single-crystal X-ray data confirmed the CaBe2Ge2-type structure, space group P4/nmm. The structures of SrAu1.76Sn2.24, SrAu2Sn2, SrAu2.16Sn1.84 (crystal A), SrAu2.16Sn1.84 (crystal B), and SrAu2.22Sn1.78 were refined from singlecrystal diffractometer data. Only the SrAu2Sn2 crystal shows complete Au-Sn ordering while all other crystals show substantial mixed occupancies on the four crystallographically independent sites of the polyanionic networks in which the strontium atoms fill cages of coordination number 16. Temperature-dependent susceptibility measurements have revealed diamagnetism for SrAu2Sn2. 119Sn Mössbauer spectroscopic data of a bulk SrAu2Sn2 sample have resolved the tetrahedral and square-pyramidal tin sites but point to substantial Au-Sn disorder.

scholarly journals Struktur- und Phasenübergangsuntersuchungen an β-Li2ZnGe/ Structure and Phase Transition Investigations on β-Li2ZnGe

1981 ◽  
Vol 36 (8) ◽  
pp. 917-921 ◽  
Author(s):  
Hans-Otto Cullmann ◽  
Heinz-Walter Hinterkeuser ◽  
Hans-Uwe Schuster
Keyword(s):  
Phase Transition ◽  
Thermal Analysis ◽  
Differential Thermal Analysis ◽  
Single Crystal ◽  
Ternary Compound ◽  
Type Structure ◽  
Crystal Data ◽  
Space Group ◽  
Cell Parameters ◽  
Structure Space

Abstract The ternary compound β-Li2ZnGe was prepared and its structure determined from powder and single crystal data. The compound crystallizes in a modified Na3As type structure, space group Ṗ̇̇̇̇̇̇̇̇̇̇̇̇̇̇3̄m 1 - D33d.The cell parameters are: a = 432.6 pm, c = 1647.0 pm, c/a= 3.83.A phase transition between a-and β-Li2ZnGe was found and the reaction of the elements lithium, zinc and germanium to a-Li2ZnGe was followed by differential thermal analysis. The temperatures and the enthalpies of transition and fusion were determined.

scholarly journals CRYSTAL STRUCTURE OF THE NEW SILICIDE Lu3Ni11.74(2)Si4

2020 ◽  
Vol 86 (5) ◽  
pp. 3-12
Author(s):  
Bohdana Belan ◽  
Mykola Manyako ◽  
Mariya Dzevenko ◽  
Dorota Kowalska ◽  
Roman Gladyshevskii
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Type Structure ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Arc Melting ◽  
Pearson Symbol ◽  
Ternary Silicide

The new ternary silicide Lu3Ni11.74(2)Si4 was synthesized from the elements by arc-melting and its crystal structure was determined by the single-crystal X-ray diffraction. The compound crystallizes in the Sc3Ni11Ge4-type: Pearson symbol hP37.2, space group P63/mmc (No. 194), a = 8.0985(16), c = 8.550(2) Å, Z = 2; R = 0.0244, wR = 0.0430 for 244 reflections. The silicide Lu3Ni11.74(2)Si4 is new member of the EuMg5.2-type structure family.

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