The Ternary Rare Earth Chromium Nitrides Ce2CrN3 and Ln3Cr10−xN11 with Ln = La, Ce, Pr

The title compounds have been prepared by annealing cold-pressed pellets of the binary nitrides LnN and CrN. Well developed crystals were obtained by recrystallization of the binary or prereacted ternary nitrides in a Li3N flux. Their structures were determined from single-crystal diffractometer data. C e2CrN3 has a U2CrN3 type structure: Immm , a = 379.0(1), b = 340.4(1), c = 1251.7(2) pm, Z = 2, R = 0.012 for 383 structure factors and 16 variables. The atomic positions of this structure are similar to those of U2IrC2 and K2NiF4. The structure may be rationalized to a first approximation with the formula (Ce+4)2[CrN3]8−. The chromium atoms are in a distorted square-planar nitrogen coordination. The CrN4-squares are linked via corner-sharing nitrogen atoms, thus forming infinite, straight - N - CrN2- N - CrN2- chains. The cubic structure of La3Cr10−xN11 (a = 1298.2(1) pm ), Ce3Cr10−xN11 (with a small homogenity range; a = 1284.3(1)-1286.1(3) pm ), and Pr3Cr10−xN11 (a = 1289.1(2) pm ) was determined for the lanthanum compound: Fm 3̄ m , Z = 8, R = 0.027 for 189 F values and 18 variables. One chromium site was found to have an occupancy of only 80.9(5)% resulting in the composition La3Cr9.24(1)N11. The nitrogen atoms occupy four atomic sites. Three of these have octahedral environments (6 La, 3 La + 3 Cr, 2 La + 4 Cr), the fourth one is surrounded by eight chromium atoms forming a cube. The chromium atoms are tetrahedrally coordinated by nitrogen atoms, and these CrN4-tetrahedra are linked via common corners and edges to form a three-dimensionally infinite polyanionic network. In addition the chromium atoms with oxidation numbers of about 2 to 3 form numerous Cr - Cr bonds, which allow to rationalize the Pauli paramagnetism of the compound.

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Quaternary Equiatomic Compounds LnZnSbO (Ln = La - Nd, Sm) with ZrCuSiAs-Type Structure

Zeitschrift für Naturforschung B ◽

10.1515/znb-1997-1205 ◽

1997 ◽

Vol 52 (12) ◽

pp. 1467-1470 ◽

Cited By ~ 20

Author(s):

Petra Wollesen ◽

Joachim W. Kaiser ◽

Wolfgang Jeitschko

Keyword(s):

Zinc Oxide ◽

Single Crystal ◽

Chemical Bonding ◽

Type Structure ◽

Variable Parameters ◽

X Ray ◽

Structure Factors ◽

Cold Pressed

Abstract The five compounds LnZnSbO (Ln = La - Nd, Sm) were prepared by annealing cold-pressed pellets of the lanthanoids, zinc oxide, and antimony, or by reacting these components in a NaCl/KCl flux. They crystallize with the tetragonal ZrCuSiAs type structure, which was refined from single-crystal X-ray data of CeZnSbO : P 4/nmm, a = 419.76(4), c = 947.4(1) pm, Z = 2, R = 0.022 for 165 structure factors and 12 variable parameters. Chemical bonding in this and the formally isotypic compound CeZn1-xSb2 is briefly discussed.

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The Crystal Structures of Re2Al, Re4Al11, and ReAl6

Zeitschrift für Naturforschung B ◽

10.1515/znb-1993-1212 ◽

1993 ◽

Vol 48 (12) ◽

pp. 1767-1773 ◽

Cited By ~ 14

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.

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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

Zeitschrift für Naturforschung B ◽

10.1515/znb-1997-0504 ◽

1997 ◽

Vol 52 (5) ◽

pp. 560-564 ◽

Cited By ~ 67

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.

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Adventitiously Obtained Rare-Earth Peroxide Complexes and Their Structural Characterisation

Australian Journal of Chemistry ◽

10.1071/ch14410 ◽

2014 ◽

Vol 67 (12) ◽

pp. 1860 ◽

Cited By ~ 12

Author(s):

Glen B. Deacon ◽

Craig M. Forsyth ◽

Dominique Freckmann ◽

Peter C. Junk ◽

Kristina Konstas ◽

...

Keyword(s):

Rare Earth ◽

Single Crystal ◽

Bulk Sample ◽

Structural Characterisation ◽

Square Planar ◽

Phenyl Mercury ◽

Oxygen Atoms

The structures of three adventitiously obtained peroxolanthanoid complexes have been determined, namely, [Yb2(Cp)4(μ-O)2/3(μ-O2)1/3(thf)2] (1) (Cp = cyclopentadienyl; thf = tetrahydrofuran), which has disorder between the bridging oxide and peroxide, [Nd2(o-PhPhForm)4(thf)4(μ-O2)] (2) (o-PhPhForm = N,N′-bis(2-phenylphenyl)formamidinate), and [Eu4(FForm)6(μ-OH)2(μ3-O2)2(μ-diglyme)2]·2diglyme (3) (FForm = N,N′-bis(2-fluorophenyl)formamidinate, diglyme = bis(2-methoxyethyl) ether). In the first two complexes, the peroxide bridges side-on between metals, whereas in the last complex, each peroxide bridges three metals through both oxygen atoms. The first complex was a single crystal amongst a bulk sample of [Yb(Cp)2(pzPh)(thf)] (pzPh = 2-(1′-pyrazolyl)phenyl), prepared by oxidation of dicyclopentadienylytterbium(ii) by bis(2-(1′-pyrazolyl)phenyl)mercury, the structure of which was also determined and showed distorted square planar stereochemistry for mercury.

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

Zeitschrift für Naturforschung B ◽

10.1515/znb-1996-0214 ◽

1996 ◽

Vol 51 (2) ◽

pp. 249-256 ◽

Cited By ~ 21

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.

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

Zeitschrift für Naturforschung B ◽

10.1515/znb-2001-1108 ◽

2001 ◽

Vol 56 (11) ◽

pp. 1143-1148 ◽

Cited By ~ 8

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.

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The Thorium Transition Metal Borides Th2TB10 (T = Fe, Co, Ni) with a Structure Very Similar to that of CaB6

Zeitschrift für Naturforschung B ◽

10.1515/znb-1995-0812 ◽

1995 ◽

Vol 50 (8) ◽

pp. 1195-1199 ◽

Cited By ~ 3

Author(s):

Thomas Konrad ◽

Wolfgang Jeitschko

Keyword(s):

Transition Metal ◽

Single Crystal ◽

Structure Type ◽

Crystal Data ◽

Variable Parameters ◽

X Ray ◽

Arc Melting ◽

Structure Factors ◽

Metal Borides ◽

Cold Pressed

The title compounds have been prepared by arc-melting cold-pressed pellets of the elemental components. They crystallize with a new structure type, which was determined from singlecrystal X-ray diffractometer data of Th2NiB10: Pbam, a = 564.6(2) pm, b = 1120.4(3) pm, c = 417.3(1) pm, Z = 2, R = 0.020 for 748 structure factors and 25 variable parameters. The structures of Th2FeB10 (a = 562.7(1) pm, b = 1126.1(3) pm, c = 418.3(2) pm) and Th2CoB10 (a = 562.4(1) pm, b = 1122.8(2) pm, c = 418.5(1) pm) were refined from single-crystal data to residuals of 0.025 (921 F values) and 0.032 (911 F values). The lattice of these ternary borides may be derived from that of ThB6 (Th2B12) with the cubic CaB6 type structure by replacing two of the linking boron atoms of adjacent B6 octahedra by a transition metal atom.

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SINGLE CRYSTAL NEUTRON DIFFRACTION STUDIES OF HCP RARE EARTH THORIUM ALLOYS

Le Journal de Physique Colloques ◽

10.1051/jphyscol:19711403 ◽

1971 ◽

Vol 32 (C1) ◽

pp. C1-1128-C1-1129

Author(s):

H. R. CHILD ◽

W. C. KOEHLER

Keyword(s):

Rare Earth ◽

Neutron Diffraction ◽

Single Crystal

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A synchrotron X-ray study of the electron density in C-type rare earth oxides

Acta Crystallographica Section B Structural Science ◽

10.1107/s0108768195013371 ◽

1996 ◽

Vol 52 (3) ◽

pp. 414-422 ◽

Cited By ~ 46

Author(s):

E. N. Maslen ◽

V. A. Streltsov ◽

N. Ishizawa

Keyword(s):

Heavy Metal ◽

Rare Earth ◽

Electron Density ◽

Approximate Symmetry ◽

Data Set ◽

X Ray ◽

Metal Atoms ◽

Structure Factors ◽

Deformation Electron Density ◽

Synthetic Crystals

Structure factors for small synthetic crystals of the C-type rare earth (RE) sesquioxides Y2O3, Dy2O3 and Ho2O3 were measured with focused λ = 0.7000 (2) Å, synchrotron X-radiation, and for Ho2O3 were re-measured with an MoKα (λ = 0.71073 Å) source. Approximate symmetry in the deformation electron density (Δρ) around a RE atom with pseudo-octahedral O coordination matches the cation geometry. Interactions between heavy metal atoms have a pronounced effect on the Δρ map. The electron-density symmetry around a second RE atom is also perturbed significantly by cation–anion interactions. The compounds magnetic properties reflect this complexity. Space group Ia{\bar 3}, cubic, Z = 16, T = 293 K: Y2O3, Mr = 225.82, a = 10.5981 (7) Å, V = 1190.4 (2) Å3, Dx = 5.040 Mg m−3, μ 0.7 = 37.01 mm−1, F(000) = 1632, R = 0.067, wR = 0.067, S = 9.0 (2) for 1098 unique reflections; Dy2O3, Mr = 373.00, a = 10.6706 (7) Å, V = 1215.0 (2) Å3, Dx = 8.156 Mg m−3, μ 0.7 = 44.84 mm−1, F(000) = 2496, R = 0.056, wR = 0.051, S = 7.5 (2) for 1113 unique reflections; Ho2O3, Mr = 377.86, a = 10.606 (2) Å, V = 1193.0 (7) Å3, Dx = 8.415 Mg m−3, μ 0.7 = 48.51 mm−1 F(000) = 2528, R = 0.072, wR = 0.045, S = 9.2 (2) for 1098 unique reflections of the synchrotron data set.

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