One-Dimensional MIIICuII Compounds with an Unprecedented, Tubelike Structural Motif(M= Rare-Earth Metal)

1992 ◽  
Vol 31 (5) ◽  
pp. 626-628 ◽  
Author(s):  
Olivier Guillou ◽  
Robert L. Oushoorn ◽  
Olivier Kahn ◽  
Kamal Boubekeur ◽  
Patrick Batail
Keyword(s):  
Rare Earth ◽  
Rare Earth Metal ◽  
Earth Metal ◽  
Structural Motif ◽  
One Dimensional

Rows of corner- and face-sharing Mg4 tetrahedra arranged as hexagonal rod packing in the hexagonal Laves phases REMg2 and the rare earth-rich phases RE9CoMg4 (RE=Y, Dy-Tm, Lu)

2018 ◽  
Vol 233 (9-10) ◽  
pp. 607-613 ◽  
Author(s):  
Sebastian Stein ◽  
Rainer Pöttgen
Keyword(s):  
Rare Earth ◽  
Rare Earth Metal ◽  
Diffraction Data ◽  
Earth Metal ◽  
Structural Motif ◽  
Induction Melting ◽  
X Ray Diffraction ◽  
Laves Phases ◽  
X Ray ◽  
The Many

Abstract Six new rare earth metal-rich intermetallic compounds RE9CoMg4 with RE=Y, Dy, Ho, Er, Tm and Lu were synthesized by induction-melting the elements in sealed niobium ampoules followed by annealing in muffle furnaces. The structures of Y9CoMg4 and Tm8.56CoMg4.44 were refined from single-crystal X-ray diffraction data: P63/mmc, a=965.65(6), c=971.07(5) pm, wR2=0.0599, 614 F2 values, 20 variables for Y9CoMg4 and a=945.20(4), c=953.11(5) pm, wR2=0.0358, 585 F2 values, 21 variables for Tm8.56CoMg4.44 (a small homogeneity range results from Tm/Mg mixing). The RE9CoMg4 phases crystallize with a coloring variant of the aristotype Co2Al5. The striking structural motif is a hexagonal rod packing of rows of corner- and face-sharing tetrahedral Mg4 clusters with Mg–Mg distances ranging from 304 to 317 pm in Y9CoMg4. These rows are similar to the hexagonal Laves phases REMg2. The space between the rows is filled with rows of face-sharing Co@Y6 trigonal prisms (TP) and empty Y6 octahedra (O) in the sequence –TP–O–O–. The many isopointal coloring variants of the aristotype Co2Al5 are briefly discussed.

Construction of a porous three dimensional rare earth metal–sulfur–ligand open framework

2015 ◽  
Vol 51 (87) ◽  
pp. 15819-15822 ◽  
Author(s):  
Jin Xu ◽  
Ting Liu ◽  
Xiaohui Han ◽  
Shanshan Wang ◽  
Dan Liu ◽  
...  
Keyword(s):  
Rare Earth ◽  
Rare Earth Metal ◽  
Three Dimensional ◽  
Earth Metal ◽  
One Dimensional ◽  
Open Framework ◽  
Sulfur Ligand ◽  
Organic Linker

By using piperazine-1,4-dicarbodithiolate (pipzdtc2−) as the organic linker and the Nd3+ cation as the inorganic motif, a 3D rare earth metal–sulfur–ligand MOF with one-dimensional channels was obtained.

Ternary Rare Earth Metal Silicides RE2RE’3Si4 with Orthorhombic Sm5Ge4 or Tetragonal Zr5Si4 Type Structure

2004 ◽  
Vol 59 (2) ◽  
pp. 174-181 ◽  
Author(s):  
Ute Ch Rodewald ◽  
Birgit Heying ◽  
Dirk Johrendt ◽  
Rolf-Dieter Hoffmann ◽  
Rainer Pöttgen
Keyword(s):  
Rare Earth ◽  
Rare Earth Metal ◽  
Earth Metal ◽  
Structural Motif ◽  
Coordination Polyhedra ◽  
Arc Melting ◽  
Metal Silicides ◽  
Trivalent State ◽  
Back Donation ◽  
Structure Calculations

Ternary silicides RE2RE′3 Si4 (RE = La, Ce; RE′= Y, Lu) were synthesized by arc-melting of the elements. Single crystals were grown by annealing the arc-molten buttons slightly below the melting points in water-cooled silica tubes in an induction furnace. Five silicides RE2RE3′Si4 were investigated by X-ray powder and single crystal diffraction: Zr5Si4 type, P41212, a = 779.4(3), c = 1441.3(9) pm, wR2 = 0.072, 1806 F2 values, 45 variables for La1.72(4)Y3.28(4)Si4, P43212, a = 769.92(7), c = 1412.3(1) pm, wR2 = 0.079, 1846 F2 values, 45 variables, BASF = 0.36(4) for La1.72(2)Lu3.28(2)Si4, P41212, a = 778.6(1), c = 1433.9(3) pm, wR2 = 0.054, 1910 F2 values, 46 variables, BASF = 0.34(4) for Ce1.82(6)Lu3.18(6)Si4, P43212, a = 778.8(3), c = 1436.0(10) pm, wR2 = 0.166, 1916 F2 values, 45 variables for Ce1.71(7)Y3.29(7)Si4, and Sm5Ge4 type, Pnma, a = 749.2(2), b = 1484.2(7), c = 780.3(2) pm, wR2 = 0.070, 1956 F2 values and 49 variables for Ce1.47(3)Y3.53(3)Si4. The local coordinations of both structure types are very similar, i. e. CN 18, 16, and 14 coordination polyhedra for the RE1, RE2, and RE3 atoms. The main structural motif is the eightfold coordination of the RE3 positions by rare earth metal atoms. These slightly distorted RERE’8 cubes are condensed via common corners (Zr5Si4 type) or via common edges (Sm5Ge4 type). All silicon atoms in these silicides form Si2 pairs at Si-Si distances ranging from 254 to 258 pm. DFT band structure calculations confirm the metallic character of both silicides and the trivalent state of cerium in Ce5Si4. The COHP analysis (Crystal Orbital Hamilton Population) of the Si-Si bonds shows a significant occupation of Si-Si antibonding orbitals, which is partially compensated by a Si-Si π*,σ*Y-4d (Ce-5d) back donation.

Phase selectivity and tunable photophysical nature of rare earth metal–organic frameworks of EuxY1−x-PTC (H3PTC = 2,4,6-pyridine tricarboxylic acid; x = 0–1)

2020 ◽  
Vol 49 (42) ◽  
pp. 14985-14994
Author(s):  
Xu-Sheng Gao ◽  
Mei-Juan Ding ◽  
Jin Zhang ◽  
Li-Duo Zhao ◽  
Xiao-Ming Ren
Keyword(s):  
Rare Earth ◽  
Solid Solutions ◽  
Rare Earth Metal ◽  
Metal Organic Frameworks ◽  
Earth Metal ◽  
Tricarboxylic Acid ◽  
Excitation Wavelength ◽  
Metal Organic ◽  
Phase Selectivity

All solid solutions (EuxY1−x-PTC, x = 0.013–0.82) are isomorphic to Eu-PTC, but different from Y-PTC, and show phase selectivity as well as excitation wavelength dependent emission.

scholarly journals Experimental Investigation of WE54 magnesium rare earth metal alloys by ageing treatment

2021 ◽  
Vol 1104 (1) ◽  
pp. 012025
Author(s):  
Sachendra ◽  
Shailesh Kumar Singh ◽  
Ujjwal ◽  
Satyajeet Kumar ◽  
Kuldeep Singh
Keyword(s):  
Experimental Investigation ◽  
Rare Earth ◽  
Rare Earth Metal ◽  
Earth Metal ◽  
Metal Alloys ◽  
Ageing Treatment
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