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Wolfgang Jeitschko - One of the best experts on this subject based on the ideXlab platform.
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preparation and crystal structure of the ternary uranium rare earth Antimonides u 2 3 r 1 3 sb 2 and u 1 2 r 1 2 3 sb 7 with mixed u r occupancy of the metal sites and a variety of antimony polyanions
Inorganic Chemistry, 2001Co-Authors: Tobias Schmidt, Wolfgang JeitschkoAbstract:The ternary Antimonides (U(2/3)R(1/3))Sb(2) (R = Y, Ce-Nd, Sm, Gd-Tm) and (U(1/2)R(1/2))(3)Sb(7) (R = Y, Gd-Ho) have been prepared by reaction of the uranium antimonide USb(2) with the corresponding rare earth Antimonides RSb(2) and an excess of elemental antimony at high temperatures. The crystal structure of the isotypic series (U(2/3)R(1/3))Sb(2) has been determined from single-crystal X-ray data of (U(0.675(9))Gd(0.325(9)))Sb(2). It is isotypic with PbCl(2): Pnma, Z = 4, a = 754.6(1), b = 419.6(1), c = 1025.7(3) pm. The compounds of the other series crystallize with a new structure type, which has been determined for (U(0.49(1))Ho(0.51(1)))(3)Sb(7): Immm, Z = 4, a = 410.1(1), b = 1447.7(3), c = 1821.2(5) pm. In both structures, the metal positions have mixed occupancy and high coordination numbers. Both structures contain numerous weak Sb-Sb bonds, thus forming a band of antimony atoms in the structure of (U(2/3)Gd(1/3))Sb(2) and a chain and a three-dimensionally infinite network of antimony atoms in the structure of (U(1/2)Ho(1/2))(3)Sb(7). Analyses of the Sb-Sb bonding within the antimony polyanions on the basis of bond-length bond-strength considerations indicate that the uranium atoms have mixed or intermediate +3/+4 valence in these compounds. The structure of (U(1/2)Ho(1/2))(3)Sb(7) may be considered as a defect variant of the structure of Ce(6)MnSb(15).
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a variety of different occupancies in isotypic compounds ternary Antimonides and bismuthides with the ideal formulast5t sb3 andt5t bi3 t ti zr hf t late transition metals and the binary antimonide ti4 80sb3 29 all crystallizing with filled mn5si3 hf5
Zeitschrift für anorganische und allgemeine Chemie, 2001Co-Authors: Joachim W Kaiser, Martin G Haase, Wolfgang JeitschkoAbstract:Fourteen new binary and ternary compounds are reported. The ternary Antimonides Ti5T ′Sb3 (T ′ = Co, Ni, Zn, Ru, Rh, Pd, Pt), T5T ′Sb3 (T = Zr, Hf; T ′ = Pd, Pt) and the bismuthides Ti5CuBi3 and Ti5ZnBi3 were synthesized by reaction of the elemental components at high temperatures. They crystallize with the hexagonal Hf5CuSn3 (“filled” Mn5Si3, Mo5Si3C) type structure. Structure refinements from single-crystal X-ray diffractometer data (Ti5–xZnSb3, Ti5–xPt1–ySb3, and Ti5–xZn1?yBi3+z) and powder diffractometer data (Ti5–xCu1–ySb3) reveal in some cases considerable deviations from the ideal composition with x, y, and z values up to 0.66. This is also the case for the “self-filled” binary phase Ti4.80Sb3.29 as is shown by a structure refinement from X-ray powder diffractometer data. The crystal structure of Ti5Sb2.85 with β-Yb5Sb3 type structure was confirmed by a refinement from single-crystal data. Eine Vielfalt von unterschiedlichen Besetzungen von Atompositionen in isotypen Verbindungen: ternare Antimonide und Wismutide mit der idealen Zusammensetzung T5T′Sb3 und T5T′Bi3 (T = Ti, Zr, Hf; T′ = Eisen- und Platin-Metalle) und das binare Antimonid Ti4,80Sb3,29, alle mit „gefullter” Mn5Si3 (Hf5CuSn3)-Struktur und Strukturverfeinerung von Ti5Sb2,85 mit β-Yb5Sb3-Struktur Es wird uber 14 neue binare und ternare Verbindungen berichtet. Die ternaren Antimonide Ti5T ′Sb3 (T ′ = Co, Ni, Zn, Ru, Rh, Pd, Pt), T5T ′Sb3 (T = Zr, Hf; T ′ = Pd, Pt) und die Wismutide Ti5CuBi3 und Ti5ZnBi3 wurden durch Reaktion der elementaren Komponenten bei hohen Temperaturen hergestellt. Sie kristallisieren mit der hexagonalen Hf5CuSn3 („gefullten” Mn5Si3, Mo5Si3C)Struktur. Strukturverfeinerungen aus Einkristall-Rontgen-Diffraktometerdaten (Ti5–xZnSb3, Ti5–xPt1–ySb3 und Ti5–xZn1?yBi3+z) sowie Pulver-Diffraktometerdaten (Ti5–xCu1–ySb3) zeigen in einigen Fallen erhebliche Abweichungen von der idealen Zusammensetzung, wobei fur x, y oder z Werte bis zu 0,66 erhalten wurden. Dies gilt auch fur die entsprechende binare Phase Ti4,80Sb3,29, wie eine Strukturverfeinerung aus Rontgen-Pulver-Diffraktometerdaten zeigt. Die Struktur von Ti5Sb2,85, isotyp mit β-Yb5Sb3, wird durch eine Verfeinerung aus Einkristalldaten bestatigt.
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ternary Antimonides lntsb3 with ln la nd sm and t v cr
Zeitschrift für Naturforschung B, 1995Co-Authors: Markus Brylak, Wolfgang JeitschkoAbstract:The title compounds were prepared by reaction of the elemental components. They crystallize in a new structure type, which was determined from single-crystal X -ray data of CeCrSb₃: Pbcm, a = 1310.8(3), b = 618.4(1), c = 607.9(1) pm, Z = 4, R = 0.029 for 648 structure factors and 32 variable parameters. The structure of the antimonide CeVSb₃ is isotypic: a = 1319.0(2), b = 623.92(8), c = 603.03(8) pm , R = 0.041 for 477 structure factors and 32 variables. The transition metal site and one of the three antimony sites were found to have partial occupancies resulting in the exact compositions CeV₀,₉₁₍₁₎Sb₂,₉₁₆₍₄₎ and CeCr₀,₉₀₁₍₉₎Sb₂,₉₀₉₍₄₎. The structures contain fractional Sb -Sb bonds with distances varying between 301,5 and 316.4 pm. The transition metal atoms have octahedral antimony coordination. These TSb₆ octahedra share faces resulting in linear infinite strings with V - V and Cr - Cr bond distances of 301.5 and 304.0 pm, respectively. The structure of these com pounds contains building elements, which are also found in Antimonides with ThCr₂Si₂, CaBe₂Ge₂, and HfCuSi₂ type structures.
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ternary arsenides acuas2 and ternary Antimonides aagsb2 a rare earth elements and uranium with hfcusi2 type structure
IEEE Journal of Solid-state Circuits, 1995Co-Authors: Markus Brylak, Manfred H Moller, Wolfgang JeitschkoAbstract:Abstract The arsenides ACuAs2 (A = Y, La-Nd, Sm, Gd-Lu) and the isotypic Antimonides AAgSb2 (A = Y, La-Nd, Sm, Gd-Tm, U) were prepared for the first time and their lattice constants are reported. Single crystals of CeAgSb2 were obtained from a NaCl/KCl flux and their structure was determined from four-circle diffractometer X-ray data: P4/nmm, a = 436.3(1) pm, c = 1069.9(4) pm, Z = 2, R = 0.017 for 381 structure factors and 12 variable parameters. CeAgSb2 is isotypic with HfCuSi2, CaMnBi2, and ZrCuSiAs. In contrast to other ternary lanthanoid transition metal Antimonides with HfCuSi2-type structure, the silver site is fully occupied. Chemical bonding in CeAgSb2 can be rationalized by the formula Ce3+Ag+Sb-Sb3-, where the superscripts indicate oxidation numbers.
Arthur Mar - One of the best experts on this subject based on the ideXlab platform.
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a new family of nonstoichiometric layered rare earth tin Antimonides resnxsb2 re la ce pr nd sm crystal structure of lasn0 75sb2
Inorganic Chemistry, 1996Co-Authors: Michael J Ferguson, Ryan W Hushagen, Arthur MarAbstract:A new class of nonstoichiometric layered ternary rare-earth tin Antimonides, RESnxSb2 (RE = La, Ce, Pr, Nd, Sm), has been synthesized through reaction of the elements at 950 °C. In the lanthanum se...
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new ternary rare earth transition metal Antimonides re3msb5 re la ce pr nd sm m ti zr hf nb
Chemistry of Materials, 1995Co-Authors: Gwenael Bollore, Michael J Ferguson, Ryan W Hushagen, Arthur MarAbstract:Investigations into ternary rare-earth transition-metal antimonide systems RE{sub x}M{sub y}Sb{sub z} have been going on for at least two decades. These studies have been carried out variously to search for new magnetic materials, to test the validity of bonding models, and perhaps most importantly, to systematize an interesting structural chemistry that is not as well understood as that of the corresponding phosphides or arsenides. Some of these Antimonides have counterparts in phosphides or arsenides, such as REMSb{sub 2} (M = Mn-Zn, Pd, Ag, Au) with the HfCuSi{sub 2} structure, REM{sub 2}Sb{sub 2} (M = Mn, Ni, Pd) with the CaBe{sub 2}-Ge{sub 2} and ThCr{sub 2}Si{sub 2} structures, and REM{sub 4}Sb{sub 12} (M = Fe, Ru, Os) with the filled skutterudite LaFe{sub 4}P{sub 12} structure. Others, such as RE{sub 3}M{sub 3}Sb{sub 4} (M = Pt, Cu, Au) and REMSb{sub 3} (M = Cr, V) are unique to Antimonides so far. The authors report here the synthesis of a new series of ternary-Antimonides RE{sub 3}MSb{sub 5} containing an early transition metal M = Ti, Zr, Hf, Nb. 28 refs., 2 figs., 3 tabs.
Michael J Ferguson - One of the best experts on this subject based on the ideXlab platform.
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a new family of nonstoichiometric layered rare earth tin Antimonides resnxsb2 re la ce pr nd sm crystal structure of lasn0 75sb2
Inorganic Chemistry, 1996Co-Authors: Michael J Ferguson, Ryan W Hushagen, Arthur MarAbstract:A new class of nonstoichiometric layered ternary rare-earth tin Antimonides, RESnxSb2 (RE = La, Ce, Pr, Nd, Sm), has been synthesized through reaction of the elements at 950 °C. In the lanthanum se...
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new ternary rare earth transition metal Antimonides re3msb5 re la ce pr nd sm m ti zr hf nb
Chemistry of Materials, 1995Co-Authors: Gwenael Bollore, Michael J Ferguson, Ryan W Hushagen, Arthur MarAbstract:Investigations into ternary rare-earth transition-metal antimonide systems RE{sub x}M{sub y}Sb{sub z} have been going on for at least two decades. These studies have been carried out variously to search for new magnetic materials, to test the validity of bonding models, and perhaps most importantly, to systematize an interesting structural chemistry that is not as well understood as that of the corresponding phosphides or arsenides. Some of these Antimonides have counterparts in phosphides or arsenides, such as REMSb{sub 2} (M = Mn-Zn, Pd, Ag, Au) with the HfCuSi{sub 2} structure, REM{sub 2}Sb{sub 2} (M = Mn, Ni, Pd) with the CaBe{sub 2}-Ge{sub 2} and ThCr{sub 2}Si{sub 2} structures, and REM{sub 4}Sb{sub 12} (M = Fe, Ru, Os) with the filled skutterudite LaFe{sub 4}P{sub 12} structure. Others, such as RE{sub 3}M{sub 3}Sb{sub 4} (M = Pt, Cu, Au) and REMSb{sub 3} (M = Cr, V) are unique to Antimonides so far. The authors report here the synthesis of a new series of ternary-Antimonides RE{sub 3}MSb{sub 5} containing an early transition metal M = Ti, Zr, Hf, Nb. 28 refs., 2 figs., 3 tabs.
Andrei A Popov - One of the best experts on this subject based on the ideXlab platform.
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spectroscopic gas analyzers based on indium phosphide antimonide and lead salt diode lasers
Spectrochimica Acta Part A: Molecular and Biomolecular Spectroscopy, 2002Co-Authors: Peter Werle, K Maurer, Robert Kormann, Robert Mucke, F Damato, T Lancia, Andrei A PopovAbstract:Currently available semiconductor lasers for spectroscopy in the near- and mid-infrared region based on direct band-to-band transitions as gallium-arsenide, indium-phosphide, Antimonides and lead-salt containing compounds will be discussed together with the main features of different tunable diode-laser absorption spectrometers for trace gas analysis. Measurements of atmospheric carbon dioxide with a room-temperature 2 m indium-phosphide laser, applications of antimonide lasers for methane and formaldehyde sensing in the 3–4 m range and a fast chemical sensor for methane flux measurements based on lead-salt diode-lasers operating near 7.8 m will be presented. Published by Elsevier Science B.V.
Ryan W Hushagen - One of the best experts on this subject based on the ideXlab platform.
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a new family of nonstoichiometric layered rare earth tin Antimonides resnxsb2 re la ce pr nd sm crystal structure of lasn0 75sb2
Inorganic Chemistry, 1996Co-Authors: Michael J Ferguson, Ryan W Hushagen, Arthur MarAbstract:A new class of nonstoichiometric layered ternary rare-earth tin Antimonides, RESnxSb2 (RE = La, Ce, Pr, Nd, Sm), has been synthesized through reaction of the elements at 950 °C. In the lanthanum se...
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new ternary rare earth transition metal Antimonides re3msb5 re la ce pr nd sm m ti zr hf nb
Chemistry of Materials, 1995Co-Authors: Gwenael Bollore, Michael J Ferguson, Ryan W Hushagen, Arthur MarAbstract:Investigations into ternary rare-earth transition-metal antimonide systems RE{sub x}M{sub y}Sb{sub z} have been going on for at least two decades. These studies have been carried out variously to search for new magnetic materials, to test the validity of bonding models, and perhaps most importantly, to systematize an interesting structural chemistry that is not as well understood as that of the corresponding phosphides or arsenides. Some of these Antimonides have counterparts in phosphides or arsenides, such as REMSb{sub 2} (M = Mn-Zn, Pd, Ag, Au) with the HfCuSi{sub 2} structure, REM{sub 2}Sb{sub 2} (M = Mn, Ni, Pd) with the CaBe{sub 2}-Ge{sub 2} and ThCr{sub 2}Si{sub 2} structures, and REM{sub 4}Sb{sub 12} (M = Fe, Ru, Os) with the filled skutterudite LaFe{sub 4}P{sub 12} structure. Others, such as RE{sub 3}M{sub 3}Sb{sub 4} (M = Pt, Cu, Au) and REMSb{sub 3} (M = Cr, V) are unique to Antimonides so far. The authors report here the synthesis of a new series of ternary-Antimonides RE{sub 3}MSb{sub 5} containing an early transition metal M = Ti, Zr, Hf, Nb. 28 refs., 2 figs., 3 tabs.
