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  • crystal structure  (19)
  • Cell & Developmental Biology
  • 1995-1999  (21)
  • 1997  (10)
  • 1995  (11)
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  • 1995-1999  (21)
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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 1385-1394 
    ISSN: 0044-2313
    Keywords: Palladium ; quaternary fluorides ; LiPdGaF6 ; RbPdAlF6 ; K1.06Pd0.95Fe1.05F6 ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Crystal Structure of LiPdGaF6, RbPdAlF6 and K1.06Pd0.95Fe1.05F6Single crystals of LiPdGaF6 (blue; trigonal, P31c-D3d2 (No. 163), a = 505.72(2), c = 923.7(2) pm; LiCaAlF6-Type [1]), RbPdAlF6 (violet; orthorhombic, Pnma-D2h16 (No. 62), a = 729.0(1), b = 711.1(1), c = 1006.5(2) pm; CsAgFeF6-Type [2]) and K1.06Pd0.95Fe1.05F6 (greenish-blue; tetragonal, P42/mbc-D4h13 (No. 135), a = 1 279.07(7), c = 800.2(1) pm; K1,08MnFeF6-Type [3]; four cycle diffractometer data, Siemens AED2) are obtained by heating the binary fluorides in sealed Pd-tubes under dry argon [solid state reaction, T ≈ 650, t ≈ 19 d (39 d, 24 d)].
    Notes: Durch Umsetzung von äquimolaren Gemengen der binären Fluoride im verschweißten Pd-Rohr unter Schutzgas [Ar, Festkörperreaktion, T = 650°C, t = 19 d (39 d, 24 d)] erhält man Einkristalle von LiPdGaF6 (blau, trigonal, P31c-D3d2 (No. 163), a = 505,72(2), c = 923,7(2) pm, LiCaAlF6-Typ [1]), RbPdAlF6 (violett, orthorhombisch, Pnma-D2h16 (No. 62), a = 729,0(1), b = 711,1(1), c = 1006,5(2) pm, CsAgFeF6-Typ [2]) sowie K1,06Pd0,95Fe1,05F6 (blau-grün, tetragonal, P42/mbc-D4h13 (No. 135), a = 1279,07(7), c = 800,2(1) pm; K1,08MnFeF6-Typ [3]; jeweils Vierkreisdiffraktometerdaten).
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 1047-1052 
    ISSN: 0044-2313
    Keywords: Zirconium fluoride ; hafnium fluoride ; ternary fluorides ; KPdMIVF7 (MIV = Zr, Hf) ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Crystal Structure of KPdMIVF7 (MIV = Zr, Hf)Blue single crystals of KPdZrF7 are obtained by heating the binary fluorides in sealed Pt-tubes under dry argon (solid state reaction, T ≍ 720°C, t ≍ 14 d). The compound crystallizes orthorhombically in the space group Pnna-D2h6 (Nr. 52); lattice parameters are a = 1 132.3(5) pm, b = 797.5(2) pm, c = 639.8(1) pm; Z = 4 (Four cycle diffractometer data, AED2). According to [F4PdF2/1ZrF5] distortet [PdF6]-octaedra are connected with pentagonal-bipyramidal [ZrF7]-polyhedra via two bridging F-, resulting in [PdZrF11]-groups. These [PdZrF11]-groups built up a threedimensional-network with K+ in its spacings. KPdHfF7 crystallizes isotypically (a = 1 136.1(3) pm, b = 796.4(2) pm und c = 638.8(1) pm; four cycle diffractometer data, AED2).
    Notes: Durch Tempern der binären Fluoride im verschweißten Pt-Rohr unter Schutzgas (Ar, Festkörperreaktion, T ≍ 720°C, t ≍ 14d) erhält man blaue Einkristalle von KPdZrF7 [eigener Strukturtyp, orthorhombisch, Pnna-D2h6 (Nr. 52); a = 1 132,3(5) pm, b = 797,5(2) pm, c = 639,8(1) pm; Z = 4; Vierkreisdiffraktometerdaten AED2]. Pd2+ ist verzerrt oktaedrisch von 6 F- umgeben, wohingegen Zr4+ pentagonalbipyramidal von 7 F- koordiniert wird. Beide Koordinationspolyeder sind gemäß [F4PdF2/1ZrF5] kantenverknüpft und bilden mit weiteren solcher [PdZrF11]-Einheiten durch Eckenverknüpfung ein dreidimensionales Raumnetz, in dessen Lücken K+ eingelagert ist. Nach Vierkreisdiffraktometerdaten (AED2) kristallisiert KPdHfF7 isotyp (a = 1 136,1(3) pm, b = 796,4(2) pm und c = 638,8(1) pm).
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 993-1000 
    ISSN: 0044-2313
    Keywords: Zirconium(IV) fluoride ; hafnium(IV) fluoride ; Cs2Cu3MIVF12 (MIV = Zr, Hf) ; crystal structure ; magnetic properties ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cs2Cu3MIVF12 (MIV = Zr, Hf) - Crystal Structure and Magnetic BehaviourColourless single crystals of Cs2Cu3ZrF12 are obtained by heating the binary fluorides in sealed Pt-tubes under dry argon (solid state reaction, T ≍ 700°C, t ≍ 7-10 d). The compound crystallizes trigonal-rhomboedrical in the space group R3m-D3d5 (Nr. 166); lattice parameters are a = 716.61(6) pm, c = 2 046.4(2) pm, Z = 3 (Four cycle diffractometer data, AED 2). The structure is dominated by layers of corner-sharing, Jahn-Teller-distorted [CuF6]-Octahedra, which are connected via regular [ZrF6]-Octahedra to stackings parallel [00.1]. Cs+-ions are located in the spacings of the octahedra-network. From powder data Cs2Cu3HfF12 with a = 716.32(4) pm, c = 2 048.6(2) pm is isotypic. Both compounds show antiferromagnetic behaviour already at temperatures about 200 K.
    Notes: Durch Umsetzung der binären Fluoride im verschweißten Pt-Rohr unter Schutzgas (Ar, Festkörperreaktion, T ≍ 700°C, t ≍ 20d) erhält man farblose Einkristalle von Cs2Cu3ZrF12. [Trigonal-rhomboedrisch, R3m-D3d5 (Nr. 166), a = 716,61(6) pm, c = 2 046,4(2) pm, Z = 3 (Vierkreisdiffraktometerdaten, AED 2)]. Strukturbestimmend sind Schichten eckenverknüpfter, Jahn-Teller-verzerrter [CuF6]-Oktaeder, welche - über reguläre [ZrF6]-Oktaeder verknüpft - Stapel entlang [00.1] bilden. In den Hohlräumen der Struktur sind Cs+-Ionen eingelagert. Nach Pulverdaten kristallisiert Cs2Cu3HfF12 mit a = 716,32(4) pm, c = 2 048,6(2) pm isotyp. Beide Stoffe zeigen bereits bei Temperaturen um 200 K antiferromagnetisches Verhalten.
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  • 4
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Molecular Reproduction and Development 40 (1995), S. 345-354 
    ISSN: 1040-452X
    Keywords: Signal transduction ; α-subunit ; β-subunit ; Peptide antisera ; Flagellum ; Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology
    Notes: Heterotrimeric G proteins play important roles as signal transducing components in various mammalian sperm functions. We were interested in the distribution of G proteins in human sperm tails. Prior to membrane preparation, spermatozoa were separated from contaminating cells which are frequently present in human ejaculates. Enriched human sperm tail membranes were generated by using hypoosmotic swelling and homogenization procedures. Antisera against synthetic peptides were used to identify G proteins in immunoblots. AS 8, an antiserum directed against an amino acid sequence that is found in most G protein α-subunits, and A 86, which detects all known pertussis toxin-sensitive α-subunits, reacted specifically with a 40-kDa protein. Antisera against individual G protein α-subunits failed to detect any specific antigens in enriched tail membranes AS 36, recognizing the ã2-subunit of G proteins, identified a 35-kDa protein in sperm tail membranes. Antisera against the 36-kDa β1-subunit did not detect any relevant proteins in the membrane fraction. Neither G protein α-subunits nor G protein β-subunits were found in the cytosol. ADP ribosylation of spermatozoal membrane or cytosolic proteins revealed no pertussis toxin-sensitive α-subunits. However, membrane preparations of nonpurified human spermatozoa contained α2 subunits, as shown immunologically and by ADP ribosylation; they most probably derived from somatic cells which are frequently present in human ejaculates. Our results stress the fact that spermatozoa need to be purified before sperm membrane preparation to avoid misinterpretations caused by contaminating cells. Furthermore, we suggest that G proteins in membranes of human sperm tails belong to a novel subtype of G protein α-subunits; the putative β-subunit was identified as a β2-subunit. © 1995 Wiley-Liss, Inc.
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  • 5
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    BioEssays 17 (1995), S. 775-784 
    ISSN: 0265-9247
    Keywords: Life and Medical Sciences ; Cell & Developmental Biology
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Biology , Medicine
    Notes: Homeotic genes are subject to transcriptional silencing, which prevents their expression in inappropriate body regions. Here, we shall focus on Drosophila, as little is known about this process in other organisms. Evidence is accumulating that silencing of Drosophila homeotic genes is conferred by two types of cis-regulatory sequences: initiation (SIL-I) and maintenance (SIL-M) elements. The former contain target sites for transient repressors with a highly localised distribution in the early embryo and the latter for constitutive repressors that are likely to be present in all cells. We discuss how SIL-I elements may cooperate with SIL-M elements to promote formation of a silencing complex. We propose that this complex consists of specific non-histone proteins, the so-called Polycomb group proteins, and that it is anchored at SIL-M elements and at the promoter.
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  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 621 (1995), S. 181-185 
    ISSN: 0044-2313
    Keywords: Copper lanthanoide oxotungstate ; CuDy5(WO4)8 ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A New Structure Type of Copper Lanthanoide Oxotungstates: CuDy5(WO4)8Single crystals of the hitherto unknown compound CuDy5(WO4)8 were prepared in closed copper tubes and investigated by X-ray technique. It shows monoclinic symmetry, space group C2h6 - C2/c, a = 19.118, b = 5.612, c = 11.518 Å, β = 111.32°, Z = 2. The crystal structure is characterized by [W4O18] groups which are connected to layers. Dy3+ shows one sided capped trigonal prisms and Cu+/Dy3+ with statistical distribution an octahedral oxygen surrounding.
    Notes: Die bisher unbekannte Verbindung CuDy5(WO4)8 wurde einkristallin in geschlossenen Kupferrohren dargestellt und röntgenographisch untersucht. Sie kristallisiert mit monokliner Symmetrie, Raumgruppe C2h6 - C2/c mit a = 19,118; b = 5,612; c = 11,518 Å; β = 111,32°; Z = 2. Die Kristallstruktur zeichnet sich durch [W4O18]-Baugruppen aus, die zu Schichten verknüpft sind. Dy3+ zeigt einfach überkappt trigonal prismatische, die in statistischer Verteilung vorliegenden Cu+/Dy3+-Ionen eine oktaedrische Sauerstoffumgebung.
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  • 7
    ISSN: 0044-2313
    Keywords: zinc, cadmium, tin, arsenic, antimony, bismuth, cobalt, copper, trithio complexes, perthio complexes, perthiodicarbonate ; synthesis ; crystal structure ; IR spectroscopy ; Raman spectroscopy ; 113Cd and 59Co NMR spectroscopy ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Simple Trithio- and Perthiocarbonato Complexes with Interesting Bond Properties: [E(CS3)2]2- (E = Sn, Zn, Cd), [E(CS3)3]3- (E = As, Sb, Bi, Co), {Cu(CS3)-}∞ and [Zn(CS4)2]2-By reactions of potassium trithiocarbonate (1) with solutions of zinc(II)- acetylacetonate, cadmium(II)-chloride, tin(II)-chloride, arsenic(III)-sulfide (suspension), antimony(III)-chloride, bismuth(III)-chloride and copper(II)-chloride in dimethyl sulfoxide, as well as of trisodium hexanitrito cobaltate(III) in water, and the precipitation of the complexes with an aqueous solution of tetraphenylphosphonium chloride the compounds (PPh4)2[Zn(CS3)2] (2), (PPh4)2[Cd(CS3)2] (3), (PPh4)2[Sn(CS3)2] (4), (PPh4)3[As(CS3)3] (5), (PPh4)3[Sb(CS3)3] (6), (PPh4)3[Bi(CS3)3] (7), (PPh4)3[Co(CS3)3] (8) and (PPh4)Cu(CS3) (9) have been isolated. (PPh4)2[Zn(CS4)2] · CH3NO2 (10) has been prepared by heating a solution of 2 in nitromethane to 60--70°C in presence of air. The reaction of 1 in dimethyl sulfoxide with an aqueous tetraphenylphosphonium chloride solution in presence of oxygen leads to (PPh4)2[C2S6] (11). The compounds have been characterized by spectroscopical studies (IR, Raman, UV/Vis, 113Cd/59Co-NMR), magnetic susceptibility measurements, powder diffractometry, elemental analyses and single crystal X-ray structure analysis (4-7, 10 and 11). The difficult growing of single crystals has been reported in detail. For crystal data see Inhaltsübersicht.
    Notes: Durch Reaktion von Lösungen von Zink(II)-acetylacetonat, Cadmium(II)-chlorid, Zinn(II)-chlorid, Arsen(III)-sulfid (Suspension), Antimon(III)- chlorid, Bismut(III)-chlorid und Kupfer(II)-chlorid in Dimethylsulfoxid - bzw. von Trinatriumhexanitritocobaltat(III) in Wasser - mit Kaliumtrithiocarbonat (1) sowie anschließender Fällung der Komplexe mit wäßriger Tetraphenylphosphoniumchlorid-Lösung wurden die Verbindungen (PPh4)2[Zn(CS3)2] (2), (PPh4)2[Cd(CS3)2] (3), (PPh4)2[Sn(CS3)2] (4), (PPh4)3[As(CS3)3] (5), (PPh4)3[Sb(CS3)3] (6), (PPh4)3[Bi(CS3)3] (7), (PPh4)3[Co(CS3)3] (8) und (PPh4)Cu(CS3) (9) isoliert. (PPh4)2[Zn(CS4)2] · CH3NO2 (10) ließ sich aus einer Lösung von 2 in Nitromethan, die in Gegenwart von Luftsauerstoff auf 60-70°C erwärmt wurde, isolieren. Bei Umsetzung von 1 in Dimethylsulfoxid mit einer wäßrigen Tetraphenylphosphoniumchlorid-Lösung in Gegenwart von Sauerstoff bildete sich (PPh4)2[C2S6] (11). Die Verbindungen wurden durch spektroskopische Methoden (IR, Raman, UV/VIS sowie 113Cd- und 59Co-NMR), Messung der magnetischen Suszeptibilität, Pulverdiffraktometrie, Elementaranalysen und Einkristall-Röntgenstrukturanalyse (4-7, 10 und 11) charakterisiert. Die schwierige Züchtung von Einkristallen wird im Detail beschrieben. 4:P1, a = 969,1(2), b = 1 335,3(3), c = 3 749,9(7) pm, α = 84,54(3)°, β = 80,88(3)°, γ= 74,90(3)°, V = 4 618(2)×106 pm3, Z = 4, R = 0,082 für 7 635 unabhängige Reflexe (Fo 〉 4σ(Fo));5:C2/c, a = 2 236,6(4), b = 1 441,0(3), c = 4 267,7(9) pm, β = 98,59(3)°, V = 13 600(15)×106 pm3, Z = 8, R = 0,130 für 3 807 unabhängige Reflexe (Fo 〉 4σ(Fo));6:P21, a = 1 555,0(9), b = 1 437,1(5), c = 1 587,6(9) pm, β = 90,30(5)°, V = 3 547(3)×106pm3, Z = 2;7:P21, a = 1 559,6(4), b = 1 425,2(4), c = 1 585,1(4) pm, β = 90,05(2)°, V = 3 523(2)×106 pm3, Z = 2, R = 0,088 für 4 206 unabhängige Reflexe (Fo 〉 4σ(Fo));10:C2/c, a = 1 049,1(4), b = 2 023,9(9), c = 2 474,7(9) pm, β = 99,93(3)°, V = 5 176(3)×106 pm3, Z = 4, R = 0,079 für 2 172 unabhängige Reflexe (Fo 〉 4σ(Fo));11:P21/c, a = 1 673,0(5), b = 1 430,8(5), c = 1 859,1(5) pm, β = 94,12(2)°, V = 4 439(2)×106 pm3, Z = 4, R = 0,086 für 4 014 unabhängige Reflexe (Fo 〉 4σ(Fo)).
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  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1201-1202 
    ISSN: 0044-2313
    Keywords: Cobalt(II) complex ; 1,2-dimethyl-5-nitro-imidazole ligand ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: Synthesis and Crystal Structure of Bis(1,2-dimetyl-5-nitro-imidazole)dichlorocobalt(II)Bis(1,2-dimethyl-5-nitro-imidazol)dichlorocobalt(II) was obtained by reaction of CoCl2 · 6 H2O with 1,2-dimethyl-5-nitro-imidazole in methanol. The compound forms blue crystals which were characterized by IR and UV-vis spectroscopy and by an X-ray crystal structure determination. Co(C5H7N3O2)2Cl2: tetragonal, space group I42d, Z = 8, a = 1142.1(1) pm, c = 2577.3(2) pm. R = 0.036 for 670 independent reflexions. The Co atom is tetrahedrally surrounded by two chlorine and two N atoms at distances of 222.8(2) and 203.5(4) pm.
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  • 9
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 1621-1624 
    ISSN: 0044-2313
    Keywords: Sodium auride thallide ; gold chains ; thallium dumb-bells, synthesis ; crystal structure ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Na4AuTl, the First Ternary Compound in the System Sodium/Gold/ThalliumSilver coloured, brittle single crystals of Na4AuTl were obtained by the reaction of NaN3, gold sponge and TlN3 at 773 K. The structure was determined from X-ray single-crystal diffractometry data: \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm space}\,{\rm group}\,{\rm Fmmm,}\,{\rm Z = 8,}\,{\rm a = 5}{\rm .453(1)}\mathop {\rm A}\limits^ \circ,\,{\rm b = 10}{\rm .006(2)}\,\,\mathop {\rm A}\limits^ \circ,\,{\rm c = 23}{\rm .387(5)}\,\mathop {\rm A}\limits^ \circ $$\end{document} Na4AuTl crystallizes in a new structure type with separated gold and thallium partial structures. These consist of linear ∞1[Au2/2] chains and [Tl2] dumb-bells. Structural relationships between Na2Au and the Na Au partial structure of Na4AuTl are discussed.
    Notes: Silberfarbene, spröde Einkristalle eines bislang unbekannten Na4AuTl wurden durch Umsetzung von NaN3, Goldschwamm und TlN3 bei 773 K erhalten. Die Struktur wurde aus Röntgen-Einkristall-Diffraktometerdaten bestimmt: \documentclass{article}\pagestyle{empty}\begin{document}$$ {\rm Raumgruppe}\,{\rm Fmmm,}\,{\rm Z = 8,}\,{\rm a = 5,453(1)}\mathop {\rm A}\limits^ \circ,\,{\rm b = 10,006(2)}\,\,\mathop {\rm A}\limits^ \circ,\,{\rm c = 23,387(5)}\,\mathop {\rm A}\limits^ \circ $$\end{document} Na4AuTl kristallisiert in einem neuen Strukturtyp mit voneinander separierten Gold- und Thallium-Teilstrukturen, die aus linearen ∞1[Au2/2]-Ketten und [Tl2]-Hanteln aufgebaut sind. Strukturbeziehungen zwischen Na2Au und der Na—Au-Teilstruktur von Na4AuTl werden diskutiert.
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  • 10
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 623 (1997), S. 362-368 
    ISSN: 0044-2313
    Keywords: Aluminium/platinum alloys ; crystal structure ; phase transitions ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The Structure of Platinum-rich Aluminium/Platinum AlloysPlatinum-rich aluminium/platinum alloys have been synthesised via a coupled reaction between aluminium oxide and platinum in a stream of hydrogen at temperatures in the region of 1200°C. The phase richest in aluminium that was prepared was the alloy Al1.16Pt2.84 which crystallises in the AuCu3 structure type. In accordance with the composition, the platinum sites are statistically occupied to a slight extent by aluminium atoms. In a phase somewhat poorer in aluminium (Al1.05Pt2.95), the edge-sharing octahedra consisting almost exclusively of platinum atoms are twisted with respect to each other. The severity of the limited tetragonal distortion which results increases with further decrease in the aluminium content in the phase. A two phase region exists between the limiting composition of this phase and that of the aluminium-poor Pt/Al mixed crystal possessing a statistical atom distribution.By heating the alloys with the slight tetragonal distortion, a second order phase transition into the cubic phase occurs whilst the alloys with a stronger tetragonal distortion undergo a corresponding phase transition which is first order. This result conforms with the idea that, in the former case, the distortion of the platinum octahedra is progressively relieved while in the second case this event results discontinously. Consequently, both the tetragonal and the cubic phase are observed simultaneously in a distinct temperature region.
    Notes: Über eine gekoppelte Reaktion konnten aus Aluminiumoxid und Platin im Wasserstoffstrom bei Temperaturen um 1200°C platinreiche Aluminium-Platin-Legierungen synthetisiert werden.Als aluminiumreichste Phase wurde die im AuCu3-Typ kristallisierende Legierung- Al1,16Pt2,84 erhalten. Entsprechend der Zusammensetzung sind Platinatomlagen zu einem geringen Anteil statistisch durch Aluminiumatome belegt. In einer etwas aluminiumärmeren Phase (Al1,05Pt2,95) sind die fast ausschließlich durch Platinatome gebildeten eckenverknüpften Oktaeder gegeneinander verdreht. Die dadurch be dingte tetragonale Verzerrung nimmt mit weiter sinkendem Aluminiumgehali zu. Zwischen der Grenzzusammensetzung dieser Phase und einem aluminiumarmen Pt-Al-Mischkristall mit statistischer Atomverteilung liegt ein Zweiphasen gebiet.Beim Aufheizen gehen Legierungen mit geringer tetragonaler Verzerrung in einem Reaktionsablauf zweiter Ordnung in die kubische Phase über, bei Legierungen mit stärkerer tetragonaler Verzerrung verläuft eine entsprechende Phasenumwandlung nach der ersten Ordnung ab. Dieses Verhalten entspricht der Vorstellung, daß im ersten Fall die Verdrehung der Platinoktaeder kontinuierlich mit steigender Temperatur aufgehoben wird, wogegen im zweiten Fall dieser Vorgang diskontinuierlich erfolgt und deshalb in einem gewissen Temperaturbereich die tetragonale und die kubische Phase nebeneinander beobachtet werden.
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