Preparation and Crystal Structure of the Isotypic Carbides Ln3.67TC6 (Ln = rare earth elements; T = Mn, Fe, Ru) and Eu3,16NiC6

1996 ◽  
Vol 51 (2) ◽  
pp. 249-256 ◽  
Author(s):  
Anne M. Witte ◽  
Wolfgang Jeitschko
Keyword(s):  
Crystal Structure ◽  
Magnetic Susceptibility ◽  
Rare Earth ◽  
Rare Earth Elements ◽  
Single Crystal ◽  
Crystal Structures ◽  
Variable Parameters ◽  
X Ray ◽  
Arc Melting ◽  
Structure Factors

Abstract The 14 carbides Ln3.67MnC6 (Ln = La-Nd) and Ln3.67TC6 (Ln = La-Nd, Sm; T = Fe, Ru) were prepared from the elemental components by arc-melting and subsequent annealing. Eu3.16NiC6 was obtained from a lithium flux. The crystal structures of these nearly isotypic, hexagonal compounds (P63/m, Z = 2) were determined from single-crystal X-ray data; La3.67- FeC6: a = 878.7(2), c = 535.1(1) pm, R = 0.052 for 548 structure factors and 25 variable parameters; Eu3.16NiC6: a -860.0(1), c = 548.2(2) pm, R = 0.015 for 606 structure factors and 25 variables. The structures differ from the previously reported Gd3Mn2C6 structure by the occupancy of one manganese position by rare earth atoms. Since the lanthanum atoms are larger than the manganese atoms, only two thirds of these manganese positions can be occupied by the lanthanum atoms in La3.67FeC6. Eu3.16NiC6 has similar atomic positions. The C-C bond distances in the C2 pairs are 130(2) and 126.5(5) pm in the La and Eu compounds, respectively. Magnetic susceptibility measurements with a SQUID magnetometer indicate La3.67FeC6 to be Pauli paramagnetic. A test for superconductivity was negative down to 3 K.

Quaternary Equiatomic Manganese Pnictide Oxides AMnPO (A = La-Nd, Sm, Gd-Dy), AMnAsO (A = Y, La-Nd, Sm, Gd-Dy, U), and AMnSbO (A = La-Nd, Sm, Gd) with ZrCuSiAs Type Structure

1997 ◽  
Vol 52 (5) ◽  
pp. 560-564 ◽  
Author(s):  
Andre T. Nientiedt ◽  
Wolfgang Jeitschko ◽  
Peter G. Pollmeier ◽  
Markus Brylak
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Single Crystal ◽  
Chemical Bonding ◽  
Type Structure ◽  
Variable Parameters ◽  
X Ray ◽  
Structure Factors ◽  
The Rare Earth

Abstract The 24 title compounds were prepared in well crystallized form by reaction of the rare earth elements (or uranium, respectively), manganese, the pnictide components, and MnO2 in a NaCl/KCl flux. They crystallize with the tetragonal ZrCuSiAs type structure (P4/nmm, Z = 2), which has been refined from single-crystal X-ray data of NdMnPO (a = 398.9(1), c = 867.4(1) pm, R = 0.026), NdMnAsO (a = 404,9(2), c = 889.3(4) pm, R = 0.025), and NdMnSbO (a = 416.5(1), c = 946.2(2) pm, R = 0.021) for 107, 190, and 124 structure factors, respectively, and 11 variable parameters each. Chemical bonding in these compounds is briefly discussed.

scholarly journals Preparation and Crystal Structure of the Carbides Ln12Re5C15 (Ln = Y, La-N d, Gd-Er)

1994 ◽  
Vol 49 (8) ◽  
pp. 1081-1088 ◽  
Author(s):  
Rainer Pöttgen ◽  
Günter Block ◽  
Wolfgang Jeitschko ◽  
Ronald K. Behrens
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Formula Unit ◽  
Variable Parameters ◽  
X Ray ◽  
Arc Melting ◽  
Structure Factors

The title compounds were prepared by arc-melting of the elemental components and sub­sequent annealing. Their crystal structure is hexagonal P 6̅ 2 m with one formula unit per cell. It was determined from single-crystal X-ray data of La12Re5C15 (a =1116.8(1) pm, c =545.3(1) pm, R = 0.060 for 287 structure factors and 27 variable parameters) and Ho12Re5C15 (ia = 1066.7(1) pm, c = 504.2(1) pm, R = 0.018 for 392 F's and 31 variables). The structures correspond to the formula Ln12[ReC3]2[Re3C3(C2)3],where the brackets indicate two differ­ent trigonal planar anionic rhenium-carbon groups. The coordination of the rhenium atoms in these polyanions seems to be compatible with the 18-electron rule.

Er5Re2C7, Tm5Re2C7, and Lu5Re2C7 with Sc5Re2C7 Type, and Yb2ReC2 with Pr2ReC2 Type Structures

1997 ◽  
Vol 52 (2) ◽  
pp. 231-236 ◽  
Author(s):  
R. Pöttgen ◽  
K. H. Wachtmann ◽  
W. Jeitschko ◽  
A. Lang ◽  
T. Ebel
Keyword(s):  
Magnetic Susceptibility ◽  
Bond Length ◽  
High Frequency ◽  
Annealing Process ◽  
Type Structure ◽  
The Other ◽  
Variable Parameters ◽  
X Ray ◽  
Arc Melting ◽  
Structure Factors

Abstract Er5Re2C7, Tm5Re2C7, and Lu5Re2C7 were prepared by arc-melting of the elemental components and subsequent annealing at 800 °C. Er5Re2C7 forms only after the annealing process, whereas the other two carbides were already present in the as cast samples. They crystallize with a Sc5Re2C7 type structure, which was refined from single-crystal X-ray data of Lu5Re2C7: Cmmm, a = 791.44(5), b = 1418.08(8), c = 332.79(2) pm, Z = 2, R = 0.037 for 544 structure factors and 21 variable parameters. The structure contains linear centrosymmetric C3 units with a C-C bond length of 133(2) pm and isolated carbon atoms in octahedral coordination of four lutetium and two rhenium atoms. The rhenium atoms within the two-dimensionally infinite polymeric sheets [Re2C4]n are electronically saturated as is indicated by the diamagnetism and the semiconductivity of this carbide. Yb2ReC2 was prepared by reacting the elements in a sealed tantalum tube with a high-frequency furnace. It crystallizes with a Pr2ReC2 type structure: Pnma, a = 645.91(6), b = 498.64(6), and c = 966.05(6) pm. Magnetic susceptibility measurements indicate the ytterbium atoms to be trivalent in this compound.

The Crystal Structures of Re2Al, Re4Al11, and ReAl6

1993 ◽  
Vol 48 (12) ◽  
pp. 1767-1773 ◽  
Author(s):  
Sabine Niemann ◽  
Wolfgang Jeitschko
Keyword(s):  
Single Crystal ◽  
Crystal Structures ◽  
Type Structure ◽  
Variable Parameters ◽  
X Ray ◽  
Lattice Constants ◽  
Structure Factors ◽  
Pauli Paramagnetism

Well-crystallized samples of the rhenium aluminides Re4Al11 and ReAl6 were obtained by reaction of rhenium with an excess of aluminum. Re4Al11 was found to be isotypic with Mn4Al11. The MnAl6 type structure of ReAl6 was confirmed. The crystal structures of both compounds were refined from single-crystal X-ray data. Re4Al11:P1̄, Z = 1, a = 516.0(1) pm, b = 896.3(2) pm, c = 516.9(1) pm, a = 90.44(1)°, β = 99.76(1)°, γ = 105.17(1)°, V = 0.2271 nm3, R = 0.036 for 2315 structure factors and 74 variable parameters. ReAl6: Cmcm, Z = 4, a = 761.0(1) pm, b = 660.5(1) pm, c = 903.4(1) pm, V = 0.4541 nm3, R = 0.013 for 711F values and 23 variables. In both structures the rhenium atoms have ten aluminum neighbors at distances from 245 to 277 pm. The Al-Al distances cover the whole range from 251 to 362 pm rather continuously. The previously reported compound Re2Al with the tetragonal MoSi2-type structure has the lattice constants a = 298.1(1) pm, c = 958.4(4) pm, V = 0.08519 nm3. ReAl6 shows Pauli-paramagnetism.

Ternary Rare Earth Metal Gold Stannides and Indides with Ordered U3Si2 and Zr3Al2-Type Structure

1994 ◽  
Vol 49 (11) ◽  
pp. 1525-1530 ◽  
Author(s):  
Rainer Pöttgen
Keyword(s):  
Crystal Structure ◽  
Rare Earth ◽  
Single Crystal ◽  
Crystal Chemistry ◽  
Rare Earth Metal ◽  
Earth Metal ◽  
Type Structure ◽  
X Ray ◽  
Arc Melting ◽  
Cscl Type

The new ternary stannides RE2Au2Sn (RE = Gd, Tb) and indides RE2Au2In (RE = Y, Gd-Tm, Lu) were synthesized by arc-melting of the elemental components and subsequent annealing at 800 °C. While Gd2Au2Sn, Tb2Au2Sn and the indides with RE = Y, Gd-Er crystallize in the ordered U3Si2 structure, Tm2Au2In and Lu2Au2In adopt the ordered Zr3Al2 structure, respectively. The crystal structure of Dy2Au2In was refined from single-crystal X- ray data: P4/mbm, Z = 2, a = 784.1(1) pm, c = 373.9(1) pm, V = 0.2299 nm3 and R = 0.028 for 342 F2 values and 12 variables. The tin (indium) atoms in these compounds occupy [RE8] square prisms and the gold atoms are surrounded by [RE6] trigonal prisms. These fragments are derived from the AlB2 and CsCl-type structures. The crystal chemistry of these com­pounds is briefly discussed.

Crystal structure of Sc3Co1.64In4 and Sc10Co9In20 from single-crystal data

2019 ◽  
Vol 74 (3) ◽  
pp. 289-295 ◽  
Author(s):  
Nataliya Gulay ◽  
Yuriy Tyvanchuk ◽  
Marek Daszkiewicz ◽  
Bohdan Stel’makhovych ◽  
Yaroslav Kalychak
Keyword(s):  
Crystal Structure ◽  
Single Crystal ◽  
Crystal Structures ◽  
Diffraction Data ◽  
Crystal Data ◽  
X Ray Diffraction ◽  
Space Group ◽  
X Ray ◽  
Arc Melting ◽  
Pure Metals

AbstractTwo compounds in the Sc-Co-In system were obtained by arc-melting of the pure metals and their crystal structures have been determined using single crystal X-ray diffraction data. The structure of Sc3Co1.64In4 (space group P6̅, а=7.6702(5), c=3.3595(2) Å, Z=1, R1=0.0160, wR2=0.0301) belongs to the Lu3Co2−xIn4 type structure, which is closely related to the ZrNiAl and Lu3CoGa5 types. The structure of Sc10Co9In20 (space group P4/nmm, а=12.8331(1), c=9.0226(1) Å, Z=2, R1=0.0203, wR2=0.0465) belongs to the Ho10Ni9In20 type, which is closely related to HfNiGa2.

Preparation, Properties, and Crystal Structure of Quaternary Silicide Carbides RCr2Si2C (R = Y, La - Nd, Sm, Gd - Ho)

2001 ◽  
Vol 56 (11) ◽  
pp. 1143-1148 ◽  
Author(s):  
Marc W. Pohlkamp ◽  
Wolfgang Jeitschko
Keyword(s):  
Crystal Structure ◽  
Bond Distance ◽  
Single Bond ◽  
Elemental Silicon ◽  
Variable Parameters ◽  
X Ray ◽  
Arc Melting ◽  
Structure Factors ◽  
Pauli Paramagnetism ◽  
Cold Pressed

The title compounds were prepared by arc-melting cold-pressed pellets of the elemental components. They crystallize with a tetragonal structure already reported for CeCr2Si2C. It was refined from single-crystal X-ray data of PrCr2S2C: P4/mmm, a - 402.2( 1) pm, c = 535.2(1) pm, Z = 1, R = 0.012 for 252 structure factors and 10 variable parameters. Magnetic susceptibility measurements with a SQUID magnetometer indicate Pauli paramagnetism for YCr2Si2C, while CeC2Si2C shows mixed valent behavior. The carbon atoms in the structure of these compounds are isolated from each other. The silicon atoms form pairs with a Si-Si distance of 245.3 pm, somewhat greater than the single-bond distance of 235.2 pm in elemental silicon. Together with the chromium atoms, the silicon pairs and carbon atoms form a three-dimensionally infinite polyanion, which has some similarity with the polyanions found in several related tetragonal structures, e.g., the structures of ThCr2Si2 and LuNi2B2C.

Ternary gallides RE4Rh9Ga5, RE5Rh12Ga7 and RE7Rh18Ga11 (RE=Y, La–Nd, Sm, Gd, Tb) – intergrowth structures with MgCu2 and CaCu5 related slabs

2017 ◽  
Vol 232 (5) ◽  
pp. 365-374
Author(s):  
Stefan Seidel ◽  
Ute Ch. Rodewald ◽  
Oliver Janka ◽  
Rainer Pöttgen
Keyword(s):  
Magnetic Susceptibility ◽  
Low Temperature ◽  
Single Crystal ◽  
Crystal Structures ◽  
Temperature Data ◽  
X Ray ◽  
Arc Melting ◽  
Pauli Paramagnetism ◽  
Intergrowth Structures ◽  
Ferromagnetic Ordering

AbstractFourteen ternary gallides RE4Rh9Ga5, RE5Rh12Ga7 and RE7Rh18Ga11 (RE=Y, La–Nd, Sm, Gd, Tb) were synthesized from the elements by arc-melting, followed by different annealing sequences either in muffle or induction furnaces. The samples were characterized through Guinier powder patterns and the crystal structures of Ce4Rh9Ga5, Ce5Rh12Ga7, Ce7Rh18Ga11, Nd5Rh10.44(4)Ga8.56(4), Nd4Rh9Ga5 and Gd4Rh9Ga5 were refined from single crystal X-ray diffractometer data. The new gallides are the n=2, 3 and 5 members of the RE2+n Rh3+3n Ga1+2n structure series in the Parthé intergrowth concept. The slabs of these intergrowth structures derive from the cubic Laves phase MgCu2 (Mg2Ni3Si as ternary variant) and CaCu5 (CeCo3B2 as ternary variant). Only the Nd5Rh10.44(4)Ga8.56(4) crystal shows Rh/Ga mixing within the Laves type slabs. Magnetic susceptibility measurements reveal Pauli paramagnetism for Y4Rh9Ga5 and Curie-Weiss paramagnetism for Gd4Rh9Ga5 and Tb4Rh9Ga5. Low-temperature data show ferromagnetic ordering at TC=78.1 (Gd4Rh9Ga5) and 55.8 K (Tb4Rh9Ga5).

The Stannides RE2Ni2Sn (RE = Pr, Ho, Er, Tm) – Structural Transition from the W2B2Co to the Mo2B2Fe Type as a Function of the Rare Earth Size

2013 ◽  
Vol 68 (1) ◽  
pp. 10-16 ◽  
Author(s):  
Birgit Heying ◽  
Ute Ch. Rodewald ◽  
Bernard Chevalier
Keyword(s):  
Rare Earth ◽  
Rare Earth Elements ◽  
Single Crystal ◽  
Earth Element ◽  
Structural Transition ◽  
Structure Type ◽  
X Ray Diffraction ◽  
X Ray ◽  
Arc Melting ◽  
The Rare Earth

The stannides RE2Ni2Sn (RE=Pr, Ho, Er, Tm) were synthesized by arc-melting of the elements and characterized by powder X-ray diffraction. Pr2Ni2Sn crystallizes with the orthorhombic W2B2Co-type structure, Immm, a=443.8(1), b=572.1(1), c=855.1(2) pm, wR2=0.0693, 293 F2 values, 13 variables. A structural transition to the tetragonal Mo2B2Fe type occurs for the heavier rare earth elements. The structures of Ho2Ni2Sn (a=729.26(9), c=366.66(7) pm, wR2=0.0504, 250 F2 values, 12 variables), Er2Ni2Sn (a=727.2(2), c=364.3(1) pm, wR2=0.0397, 262 F2 values, 12 variables), and Tm2Ni2Sn (a=725.2(1), c=362.8(1) pm, wR2=0.0545, 258 F2 values, 12 variables) were refined from single-crystal diffractometer data. The switch in structure type is driven by the size of the rare earth element. The [Ni2Sn] substructures are composed of Ni2Sn2 squares and Ni4Sn2 hexagons in Pr2Ni2Sn, and of Ni3Sn2 pentagons in Er2Ni2Sn. The Ni4Sn2 hexagons and Ni3Sn2 pentagons exhibit Ni2 pairs with Ni-Ni distances of 247 pm in Pr2Ni2Sn, and of 250 pm in Er2Ni2Sn.

scholarly journals Hydroflux syntheses and crystal structures of hydrogarnets Ba3[RE(OH)6]2 (RE = Sc, Y, Ho–Lu)

2020 ◽  
Vol 75 (11) ◽  
pp. 951-957
Author(s):  
Ralf Albrecht ◽  
Florian Graßme ◽  
Thomas Doert ◽  
Michael Ruck
Keyword(s):  
Crystal Structure ◽  
Rare Earth ◽  
Single Crystal ◽  
Crystal Structures ◽  
Crystal Structure Data ◽  
X Ray Diffraction ◽  
Interatomic Distances ◽  
Space Group ◽  
X Ray ◽  
Rhombic Dodecahedra

AbstractColorless crystals of the barium rare earth hydrogarnets Ba3[RE(OH)6]2 (RE = Sc, Y, Ho–Lu) were synthesized under hydroflux conditions with KOH at about T = 200 °C starting from the respective RE2O3 and Ba (NO3)2. Single-crystal X-ray diffraction analysis on these distorted rhombic dodecahedra revealed the cubic space group Ia$‾{3}$d (no. 230). The crystal structures of the hydrogarnets Ba3[RE(OH)6]2 are discussed and compared with those of other hydrogarnets. The occurrence of additional reflections, which do not fulfill the reflection conditions of Ia$‾{3}$d, is analyzed and described by Renninger or λ/2 effects. A correlation is established between the space group adopted by a hydrogarnet and characteristic interatomic distances. In addition, single-crystal structure data of the strontium indium hydrogarnet Sr3[In(OH)6]2 are provided.

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