Li3Ce5Ge4, ein neuer Typ eines ternären Germanids des Lithiums mit Selten-Erd-Metallen Li3Ce5Ge4, a New Type of Ternary Compound of Lithium with Rare Earth Metal and Germanium

Abstract The ternary compound Li3Ce5Ge4 has been prepared and structurally characterized. It crystallizes orthorhombically (a = 1885 pm, b = 694.7 pm, c = 447.6 pm, space group B 2 mm). The structure shows germanium chains in a three-dimensional network of metal atoms.

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Synthese und Kristallstrukturen von Seltenerdmetall-Antimoniden des Palladiums / Synthesis and Crystal Structures of Antimonides of Rare-Earth Metals and Palladium

Zeitschrift für Naturforschung B ◽

10.1515/znb-2006-0104 ◽

2006 ◽

Vol 61 (1) ◽

pp. 17-22 ◽

Cited By ~ 5

Author(s):

Anette Imre ◽

Albrecht Mewis

Keyword(s):

Rare Earth ◽

Rare Earth Metal ◽

Three Dimensional ◽

Earth Metal ◽

Type Structure ◽

X Ray ◽

Metal Atoms ◽

New Compounds ◽

Ray Methods ◽

The Rare Earth

The new compounds Pr3Pd6Sb5 (a = 13.442(3), b = 4.442(1), c = 9.994(2) Å ), Nd3Pd6Sb5 (a = 13.412(3), b = 4.431(1), c = 9.962(2) Å), and Gd3Pd6Sb5 (a = 13.293(2), b = 4.397(1), c = 9.881(2) Å) are isotypic and crystallize with the Ce3Pd6Sb5 type structure (Pmmn; Z = 2). The rare-earth metal atoms are arranged in form of three pseudo-body-centered subcells, whereas Pd and Sb atoms form a three-dimensional arrangement derived from the well-known ThCr2Si2 and CaBe2Ge2 structures. GdPdSb (a = 4.566(1), c = 7.444(1) Å) and DyPdSb (a = 4.545(1), c = 7.354(1) Å) crystallize with an ordered variant of the CaIn2 type structure (P63mc; Z = 2), also called as LiGaGe type, with slightly puckered hexagon nets of Pd and Sb atoms, which trigonally coordinate each other. In this series a decreasing radius of the rare-earth metal allows a tetrahedral non-metal environment of the Pd atoms and accordingly ScPdSb (a = 6.310(1) Å) forms the MgAgAs type structure (F4̄3m; Z = 4), a filled variant of the sphalerite type. The antimonides were prepared by heating mixtures of the elements at 600 °C and subsequent annealing at 900 - 1100 °C. Their structures have been determined by single-crystal X-ray methods.

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ChemInform Abstract: LITHIUM CERIUM GERMANIDE (LI3CE5GE4), A NEW TYPE OF TERNARY COMPOUND OF LITHIUM WITH RARE EARTH METAL AND GERMANIUM

Chemischer Informationsdienst ◽

10.1002/chin.198001030 ◽

1980 ◽

Vol 11 (1) ◽

Author(s):

A. CZYBULKA ◽

H.-U. SCHUSTER

Keyword(s):

Rare Earth ◽

Ternary Compound ◽

Rare Earth Metal ◽

Earth Metal ◽

New Type

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Osmium and magnesium: structural segregation in the rare earth-rich intermetallics RE4OsMg (RE=La–Nd, Sm) and RE9TMg4 (RE=Gd, Tb)

Zeitschrift für Naturforschung B ◽

10.1515/znb-2019-0070 ◽

2019 ◽

Vol 74 (6) ◽

pp. 519-525 ◽

Cited By ~ 1

Author(s):

Theresa Block ◽

Sebastian Stein ◽

Lukas Heletta ◽

Rainer Pöttgen

Keyword(s):

Rare Earth ◽

Powder Diffraction ◽

Rare Earth Metal ◽

Rare Earth Metals ◽

Three Dimensional ◽

Earth Metal ◽

Intermetallic Phases ◽

Induction Melting ◽

X Ray ◽

Dimensional Network

AbstractTernary rare earth metal-rich intermetallic phases containing osmium and magnesium were obtained by induction melting of the elements in sealed niobium ampoules under argon followed by annealing in muffle furnaces. The large rare earth elements form the series of Gd4RhIn-type (F4̅3m) intermetallicsRE4OsMg withRE = La–Nd and Sm, while the smaller rare earth metals gadolinium and terbium form the Y9CoMg4-type (P63/mmc) phases Gd9OsMg4and Tb9OsMg4. All samples were characterized by X-ray powder diffraction (Guinier technique). The structures of Ce4Os0.973Mg1.027(a = 1406.54(7) pm,wR2 = 0.0478), Nd4Os0.978Mg1.022(a = 1402.00(7) pm,wR2 = 0.0463), Sm4Os0.920Mg1.080(a = 1387.33(5) pm,wR2 = 0.0378) and Gd9OsMg4(a = 971.01(5),c = 980.43(5) pm,wR2 = 0.0494) were refined from single-crystal X-ray diffractometer data. The threeRE4OsMg phases show small degrees of Os/Mg mixing, as is frequently observed for Rh/In in Gd4RhIn-type intermetallics. The basic building units in both structures are osmium-centeredRE6trigonal prisms that are condensed with emptyRE6octahedra. The magnesium atoms in both types build Mg4tetrahedra. The latter are isolated (312 pm Mg–Mg in Ce4OsMg) and incorporated within the three-dimensional network of prisms and octahedra in theRE4OsMg phases while one observes rows of corner- and face-sharing tetrahedra in Gd9OsMg4(305 and 314 pm Mg–Mg). In both structure types direct Os–Mg bonding is not observed.

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Ternary Thallides REMgTl (Re = Y, La – Nd, Sm, Gd – Tm, Lu)

Zeitschrift für Naturforschung B ◽

10.1515/znb-2005-0305 ◽

2005 ◽

Vol 60 (3) ◽

pp. 265-270 ◽

Cited By ~ 9

Author(s):

Rainer Kraft ◽

Rainer Pöttgen

Keyword(s):

Rare Earth ◽

Single Crystal ◽

Rare Earth Metal ◽

High Frequency ◽

Three Dimensional ◽

Earth Metal ◽

X Ray ◽

Sample Chamber ◽

Trigonal Prismatic Coordination ◽

Trigonal Prismatic

The rare earth metal (RE)-magnesium-thallides REMgTl (RE = Y, La-Nd, Sm, Gd-Tm, Lu) were prepared from the elements in sealed tantalum tubes in a water-cooled sample chamber of a high-frequency furnace. The thallides were characterized through their X-ray powder patterns. They crystallize with the hexagonal ZrNiAl type structure, space group P62m, with three formula units per cell. Four structures were refined from X-ray single crystal diffractometer data: α = 750.5(1), c = 459.85(8) pm, wR2 = 0.0491, 364 F2 values, 14 variables for YMgTl; α = 781.3(1), c = 477.84(8) pm, wR2 = 0.0640, BASF = 0.09(2), 425 F2 values, 15 variables for LaMgTl; α = 774.1(1), c = 473.75(7) pm, wR2 = 0.0405, 295 F2 values, 14 variables for CeMgTl; a = 760.3(1), c = 465.93(8) pm, wR2 = 0.0262, 287 F2 values, 14 variables for SmMgTl. The PrMgTl, NdMgTl, GdMgTl, TbMgTl, and DyMgTl structures have been analyzed using the Rietveld technique. The REMgTl structures contain two cystallographically independent thallium sites, both with tri-capped trigonal prismatic coordination: Tl1Mg3RE6 and Tl2Mg6RE3. Together the magnesium and thallium atoms form three-dimensional [MgTl] networks with Mg-Mg distances of 327 and Mg-Tl distances in the range 299 - 303 pm (data for CeMgTl)

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Rare Earth-rich Magnesium Compounds RE4RhMg (RE = Y, La–Nd, Sm, Gd–Tm, Lu)

Zeitschrift für Naturforschung B ◽

10.1515/znb-2007-0503 ◽

2007 ◽

Vol 62 (5) ◽

pp. 642-646 ◽

Cited By ~ 19

Author(s):

Selcan Tuncel ◽

Ute Ch. Rodewald ◽

Bernard Chevalier ◽

Rainer Pöttgen

Keyword(s):

Rare Earth ◽

High Frequency ◽

Three Dimensional ◽

Earth Metal ◽

X Ray Diffraction ◽

X Ray ◽

Dimensional Network ◽

Magnesium Compounds ◽

Rare Earth Coordination ◽

Trigonal Prismatic

Abstract The series of magnesium compounds RE4RhMg (RE = Y, La-Nd, Sm, Gd-Tm, Lu) was prepared by high-frequency melting of the elements in sealed tantalum tubes. All samples were investigated by powder X-ray diffraction. The structures with RE = Sm, Gd, Dy, Ho, and Er as rare earth metal components were refined from single crystal diffractometer data: Gd4RhIn-type, F4̄3m, Z = 16, a = 1392.1(1) pm, wR2 = 0.060, 616 F2 values, 19 variables for Sm4RhMg, a = 1380.8(2) pm, wR2 = 0.071, 530 F2 values, 19 variables for Gd4RhMg, a = 1366.9(1) pm, wR2 = 0.070, 594 F2 values, 20 variables for Dy4RhMg, a = 1355.7(2) pm, wR2 = 0.077, 578 F2 values, 20 variables for Ho3.52RhMg1.48, and a = 1355.4(2) pm, wR2 = 0.075, 559 F2 values, 20 variables for Er3.94RhMg1.06 .The rhodium atoms have slightly distorted trigonal prismatic rare earth coordination. Condensation of the RhRE6 prisms leads to a three-dimensional network which leaves large voids that are filled by regular Mg4 tetrahedra with a Mg-Mg distance of 312 pm in Sm4RhMg. The magnesium atoms have twelve nearest neighbors (3 Mg + 9 RE) in icosahedral coordination. In the structures with holmium and erbium, the RE1 positions which are not involved in the trigonal prismatic network exhibit RE1/Mg mixing. Shortest distances occur for Sm-Rh (286 pm) within the rigid three-dimensional network of condensed trigonal prisms.

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