Intermediate-valent Ce23Ru7Mg4 and RE23Ru7Mg4 (RE = La, Pr, Nd) with Pr23Ir7Mg4-type Structure

2009 ◽  
Vol 64 (11-12) ◽  
pp. 1345-1352 ◽  
Author(s):  
Stefan Linsinger ◽  
Matthias Eul ◽  
Wilfried Hermes ◽  
Rolf-Dieter Hoffmann ◽  
Rainer Pöttgen
Keyword(s):  
Magnetic Susceptibility ◽  
Rare Earth ◽  
Single Crystal ◽  
Magnetic Moment ◽  
Induction Furnace ◽  
Type Structure ◽  
Space Group ◽  
Structure Space ◽  
Magnesium Compounds ◽  
Intermediate Valent

The rare earth-rich magnesium compounds RE23Ru7Mg4 (RE = La, Ce, Pr, Nd) were synthesized from the elements in sealed tantalum ampoules in an induction furnace. They crystallize with the hexagonal non-centrosymmetric Pr23Ir7Mg4-type structure, space group P63mc. The structures of La23Ru6.88(1)Mg4 (a = 1017.7(4), c = 2286.5(5) pm, wR2 = 0.0277, 2708 F2, 71 variables), Ce23Ru7Mg4 (a = 993.5(3), c = 2243.9(8) pm, wR2 = 0.0573, 2268 F2, 70 variables), and Pr23Ru7Mg4 (a = 996.8(3), c = 2241.5(6) pm, wR2 = 0.0492, 2565 F2, 70 variables) have been refined from single-crystal diffractometer data. The structures are built up from complex threedimensional networks of edge- and corner-sharing RE6Ru trigonal prisms. Cavities within these networks are filled by slightly elongated Mg4 tetrahedra (311 - 315 pm in Pr23Ru7Mg4) and RE6 octahedra. The cerium compound has an a parameter which is even smaller than that of Nd23 Ru7Mg4, indicating intermediate-valent cerium. This was confirmed by magnetic susceptibility measurements. Ce23Ru7Mg4 shows an average, reduced magnetic moment of 2.01 μB/Ce atom. Pr23Ru7Mg4 contains stable trivalent praseodymium (3.64 μB/Pr atom)

Tm4IrIn and Lu4PtIn – In4 tetrahedra embedded in RE 22 polyhedra

2021 ◽  
Vol 0 (0) ◽  
Author(s):  
Nataliya L. Gulay ◽  
Maximilian Kai Reimann ◽  
Yaroslav M. Kalychak ◽  
Rainer Pöttgen
Keyword(s):  
Magnetic Susceptibility ◽  
Rare Earth ◽  
Single Crystal ◽  
Induction Furnace ◽  
Magnetic Ordering ◽  
Type Structure ◽  
Crystal Chemical ◽  
X Ray ◽  
Structure Space ◽  
Thulium Atom

Abstract The rare earth-rich indides Tm4IrIn and Lu4PtIn were synthesized by reaction of the elements in sealed tantalum ampules in an induction furnace. Tm4IrIn (a = 1340.77(4) pm) and Lu4PtIn (a = 1338.0(1) pm) crystallize with the Gd4RhIn-type structure, space group F 4 ‾ 3 m $F‾{4}3m$ . The Lu4PtIn structure was refined from single crystal X-ray diffractometer data: wR = 0.0524, 517 F 2 values and 20 variables. The striking crystal chemical motif is the fcc packing of In4 tetrahedra with 318 pm In–In. The Lu4PtIn structure is closely related to the structures of Lu13Ni6In, Lu14Pd3In3 and Lu20Ir5In3 which all show icosahedral indium coordination and different condensation patterns that build up the indium substructure that consists of a dumbbell in Lu14Pd3In3 and a triangle in Lu20Ir5In3. The results of magnetic susceptibility measurements indicate Curie-Weiss paramagnetism for Tm4IrIn (7.76(1) µB per thulium atom) without magnetic ordering down to 2.5 K. Lu4PtIn is Pauli-paramagnetic.

Ternary Antimonides RE4T7Sb6 (RE=Gd–Lu; T =Ru, Rh) with Cubic U4Re7Si6-type Structure

2013 ◽  
Vol 68 (9) ◽  
pp. 971-978 ◽  
Author(s):  
Inga Schellenberg ◽  
Ute Ch. Rodewald ◽  
Christian Schwickert ◽  
Matthias Eul ◽  
Rainer Pöttgen
Keyword(s):  
Magnetic Susceptibility ◽  
Single Crystal ◽  
Magnetic Moment ◽  
Induction Furnace ◽  
X Ray Diffraction ◽  
Temperature Dependent ◽  
X Ray ◽  
Antiferromagnetic Ordering ◽  
Arc Melting ◽  
Intermediate Valent

The ternary antimonides RE4T7Sb6 (RE=Gd-Lu; T =Ru, Rh) have been synthesized from the elements by arc-melting and subsequent annealing in an induction furnace. The samples have been characterized by powder X-ray diffraction. Four structures were refined on the basis of single-crystal X-ray diffractometer data: U4Re7Si6 type, space group Im3m with a=862.9(2) pm, wR2=0.0296, 163 F2 values for Er4Ru7Sb6; a=864.1(1) pm, wR2=0.1423, 153 F2 values for Yb4Ru7Sb6; a=872.0(2) pm, wR2=0.0427, 172 F2 values for Tb4Rh7Sb6; and a=868.0(2) pm, wR2=0.0529, 154 F2 values for Er4Rh7Sb6, with 10 variables per refinement. The structures have T1@Sb6 octahedra and slightly distorted RE@T26Sb6 cuboctahedra as building units. The distorted cuboctahedra are condensed via all trapezoidal faces, and this network leaves octahedral voids for the T1 atoms. The ruthenium-based series of compounds was studied by temperature-dependent magnetic susceptibility measurements. Lu4Ru7Sb6 is Pauli-paramagnetic. The antimonides RE4Ru7Sb6 with RE=Dy, Ho, Er, and Tm show Curie-Weiss paramagnetism. Antiferromagnetic ordering occurs at 10.0(5), 5.1(5) and 4.0(5) K for Dy4Ru7Sb6, Ho4Ru7Sb6 and Er4Ru7Sb6, respectively, while Tm4Ru7Sb6 remains paramagnetic. Yb4Ru7Sb6 is an intermediate-valent compound with a reduced magnetic moment of 3.71(1) μB per Yb as compared to 4.54 μB for a free Yb3+ ion

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.

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.

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.

Structure and Magnetic Properties of GdPt2In and GdPt2Sn

2009 ◽  
Vol 64 (2) ◽  
pp. 170-174 ◽  
Author(s):  
Birgit Heying ◽  
Ute Ch. Rodewald ◽  
Wilfried Hermes ◽  
Rainer Pöttgen
Keyword(s):  
Magnetic Properties ◽  
Magnetic Susceptibility ◽  
Single Crystal ◽  
Intermetallic Compounds ◽  
Coordination Number ◽  
Magnetic Moment ◽  
Space Group ◽  
X Ray ◽  
Arc Melting ◽  
Experimental Magnetic Moment

The platinum-rich intermetallic compounds GdPt2In and GdPt2Sn were synthesized by arc-melting of the elements and subsequent annealing. The structures were refined from single crystal X-ray diffractometer data: ZrPt2Al type, space group P63/mmc, a = 455.1(1), c = 899.3(3) pm, wR2 = 0.0361, 166 F2 values, 9 variables for GdPt2In, and a = 453.2(1), c = 906.5(2) pm, wR2 = 0.0915, 166 F2 values, 9 variables for GdPt2Sn. The platinum and indium (tin) atoms build up threedimensional [Pt2In] and [Pt2Sn] networks with short Pt-In (Pt-Sn) distances and Pt2 dumb-bells (290 and 297 pm in GdPt2In and GdPt2Sn). The gadolinium atoms have coordination number 14 with 8 Pt and 6 In (Sn) neighbors. Magnetic susceptibility measurements on GdPt2In show Curie-Weiss behavior with an experimental magnetic moment of 8.06(2) μB/Gd atom. GdPt2In orders ferromagnetically at 27.7(2) K

GdCuMg with ZrNiAl-type structure – an 82.2 K ferromagnet

2017 ◽  
Vol 72 (7) ◽  
pp. 511-515 ◽  
Author(s):  
Sebastian Stein ◽  
Lukas Heletta ◽  
Rainer Pöttgen
Keyword(s):  
Magnetic Susceptibility ◽  
Single Crystal ◽  
Magnetic Moment ◽  
Type Structure ◽  
Induction Melting ◽  
X Ray Diffraction ◽  
Muffle Furnace ◽  
Temperature Dependent ◽  
X Ray ◽  
Experimental Magnetic Moment

AbstractGdCuMg has been synthesized by induction-melting of the elements in a sealed niobium ampoule followed by annealing in a muffle furnace. The sample was studied by powder and single crystal X-ray diffraction: ZrNiAl type, P6̅2m (a=749.2(4), c=403.3(1) pm), wR2=0.0242, 315 F2 values and 15 variables. Temperature dependent magnetic susceptibility measurements have revealed an experimental magnetic moment of 8.54(1) μB per Gd atom. GdCuMg orders ferromagnetically below TC=82.2(5) K and based on the magnetization isotherms it can be classified as a soft ferromagnet.

scholarly journals NaBeAs(Sb) – Ternäre Phasen im „aufgefüllten“ NiAs(Ni2In)-Typ / NaBeAs(Sb) – Ternary Phases in a „Filled“ NiAs(Ni2In)-Structure

1977 ◽  
Vol 32 (10) ◽  
pp. 1133-1138 ◽  
Author(s):  
Christoph Tiburtius ◽  
Hans-Uwe Schuster
Keyword(s):  
Single Crystal ◽  
Structure Determination ◽  
Type Structure ◽  
Crystal Data ◽  
Space Group ◽  
Lattice Constants ◽  
Structure Space

NaBeAs and NaBeSb crystallize in a modified Ni2In-type-structure, space group P 63/mmc–D6h4. Preparation and structure determination with powder and single crystal data are described. The bonds and the structure are discussed in comparison with corresponding compounds of the formula AMeIIX. The lattice constants are:NaBeAs: α = 3,820(5), c = 8,948(9), c/α = 2,34;NaBeSb: α = 4,144(5), c = 9,320(9), c/α = 2,25.

Platinum-Germanium Ordering in the Germanides REPtGe with the Heavy Rare Earth Elements

2009 ◽  
Vol 64 (4) ◽  
pp. 383-387 ◽  
Author(s):  
Ute Ch. Rodewald ◽  
Birgit Heying ◽  
Rolf-Dieter Hoffmann ◽  
Dirk Niepmann ◽  
Rainer Pöttgen
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Single Crystal ◽  
Three Dimensional ◽  
Type Structure ◽  
Crystal Chemical ◽  
Heavy Rare Earth ◽  
Structure Space ◽  
Arc Melting ◽  
Heavy Rare Earth Elements

The equiatomic germanides REPtGe with the heavy rare earth elements (RE) have been reinvestigated with respect to platinum-germanium ordering. The compounds were prepared by arc-melting of the elements followed by annealing for two weeks at 1070 K. The REPtGe germanides crystallize with the TiNiSi-type structure, space group Pnma. The structures of ErPtGe (a = 692.01(5), b = 432.03(4), c = 753.19(5) pm, wR2 = 0.0523, 435 F2, 20 variables) and the new germanide LuPtGe (a = 683.1(1), b = 429.2(1), c = 750.3(1) pm, wR2 = 0.0696, 358 F2, 20 variables) have been refined from single crystal diffractometer data. These structures exhibit three-dimensional [PtGe] networks with strong Pt-Ge intra- (251 - 255 pm in LuPtGe) and weaker interlayer (272 pm in LuPtGe) interactions. The crystal chemical peculiarities of the whole REPtGe series are briefly discussed.

Sign in / Sign up

Export Citation Format

Share Document