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  • 1
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 2021-2030 
    ISSN: 0044-2313
    Keywords: Cesium Praseodymium(III) Acetate ; Synthesis ; Crystal Structure ; Thermolysis ; Evolved gas analysis (EGA) ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Cs2(H3O)Pr(CH3COO)6 and Cs2Pr(CH3COO)5: Synthesis, Crystal Structures and Thermolysis. Analogous Acetates with Lanthanum through TerbiumSingle crystals of Cs2(H3O)Pr(CH3COO)6 are obtained as green plates from an acetic acid solution (≈50%) of Cs2CO3 and Pr(CH3COO)3 · 1,5 H2O. The crystal structure monoclinic, Cm, Z = 2, a = 1 540.4(4), b = 691.3(2), c = 1 221.5(4) pm, β = 104.60(5)°, Vm = 379.1(2) cm3/mol, R = 0.040, Rw = 0.035 was determined from four-circle-diffractometer data. The structure consists of monomeric Pr(CH3COO)3 units, in which Pr3+ is surrounded by nine oxygen atoms. These monomers are linked together to infinite layers parallel (001) by common acetate oxygen atoms with two „molecules“ of Cs(CH3COO). Together with an additional acetate ion coordinated to one of the Cs+ ions the composition of the layers is [Cs2Pr(CH3COO)6]-. Between these layers H3O+ is located for electroneutrality. Thermal decomposition of Cs2(H3O)Pr(CH3COO)6 was examined with thermoanalytical methods (TG/DTA with coupled gas analysis), Guinier-Simon technique and IR spectroscopy: beginning at 70°C the compound looses water and acetic acid. It decomposes topotactically to Cs2Pr(CH3COO)5. At 270°C this acetate decomposes to Cs2CO3 and Pr2O2CO3 which emits CO2 at 600°C form ing Pr2O3or PrO2-x Single crystals of Cs2Pr(CH3COO)5 were obtained from Pr(CH3COO)3, in molten Cs(CH3COO) at about 200°C. The crystal structure tetragonal, P43, Z = 4, a = 1 174,5(2), c = 1 480,5(3) pm, Vm = pin,307,5(1) cm3/mol, R = 0,061, Rw= 0,031 again consists of Pr(CH3COO)3, monomers where Pr3+ has 9 oxygen ligands in its first coordination sphere. They are linked together by two ”molecules“ of cesium acetate to infinite chains along [00l] around the 4, screw axis. There are also acetate bridges between these chains. Isotypic compounds Cs2(H3O)M(CH3COO)6 and Cs2M(CH3COO)5, and Cs2M(CH3COO)5with M = La—Tb, were obtained from acetic acid solutions or thermal decomposition and were characterized by X-ray Guinier techniques.
    Notes: Einkristalle von Cs2(H3O)Pr(CH3COO)6 wurden in Form grüner Plättchen aus stark essigsaurer Lösung (≈50%ig) von Cs2CO3 und Pr(CH3COO)3 · 1,5 H2O gezüchtet. Die Kristallstruktur monoklin, Cm, Z = 2, a = 1 540,4(4), b = 691,3(2), c = 1 221,5(4) pm, β = 104,60(5)°, Vm = 379,1(2) cm3/mol, R = 0,040, Rw = 0,035 wurde anhand von Vierkreisdiffraktometerdaten bestimmt. In der Kristallstruktur liegen monomere Pr(CH3COO)3-Einheiten vor, in denen Pr3+ neunfach von Sauerstoff umgeben ist. Zwei „Moleküle“ Cs(CH3COO) verknüpfen diese Monomeren über Sauerstoffatome zu Schichten parallel (001). Dabei wird ein Cs+-Ion von einem weiteren Acetation koordiniert, so daß sich die Schichtzusammensetzung zu [Cs2Pr(CH3COO)6]- ergibt. Zwischen den Schichten befinden sich H3O+-Ionen zum Ladungsausgleich. Das thermische Verhalten von Cs2(H3O)Pr(CH3COO)6 wurde mittels TG/DTA mit simultaner Zersetzungsgasanalyse, Guinier-Simon-Technik und IR-Spektroskopie an den festen Thermolyseprodukten untersucht: Schon ab 70°C verliert Cs2(H3O)Pr(CH3COO)6 Wasser und Essigsäure und wird in topotaktischer Reaktion zu Cs2Pr(CH3COO)5 abgebaut. Die weitere Zersetzung beginnt bei ungefähr 270°C, wobei Cs2CO3 und wohl Pr2O2CO3 gebildet werden, das unter Abgabe von CO2 bei 600°C in Pr2O3 bzw. PrO2-x (je nach Reaktionsführung) übergeht. Einkristalle von Cs2Pr(CH3COO)5 wurden durch die Reaktion von Pr(CH3COO)3 mit geschmolzenem Cs(CH3COO) bei 200°C erhalten. Die Kristallstruktur tetragonal, Raumgruppe P43, Z = 4, a = 1 174,5(2), c = 1 480,5(3) pm, Vm = 307,5(1) cm3/mol, R = 0,061, Rw = 0,031 enthält ähnliche Monomere Pr(CH3COO)3 wie Cs2(H3O)Pr(CH3COO)6. Sie werden durch zwei „Moleküle“ Cs(CH3COO) verbunden, so daß unendliche Ketten in Form von Wendeln um die Schraubenachsen 43 entstehen, die aber auch in Richtung [100] und [010] über Acetationen verknüpft sind. Die jeweils isotypen Verbindungen Cs2(H3O)M(CH3COO)6 und Cs2M(CH3COO)5, M = La—Tb, wurden aus Lösung bzw. durch thermischen Abbau hergestellt und mittels Pulver-Röntgenmethoden charakterisiert.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
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  • 2
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 1465-1473 
    ISSN: 0044-2313
    Keywords: Cesium Lutetium(III) Acetate ; Synthesis ; Crystal Structure ; Thermolysis ; Evolved Gas Aalysis (EGA) ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Ternary Acetates of the Lanthanides with Cesium: Dimers in CsLu(CH3COO)4 and Trimers in Cs2[Lu3(CH3COO)10(OH)(H2O)]. Synthesis, Crystal Structures, ThermolysisSingle crystals of CsLu(CH3COO)4 and Cs2[Lu3(CH3COO)10(OH)(H2O)] were obtained from an aqueous solution of lutetium and cesium acetate in a 1:1 molar ratio. The crystal structures (CsLu(CH3COO)4: monoclinic, P21/n (no. 14), Z = 8, a = 1 293.1(2), b = 1 323.8(2), c = 1 622.5(3) pm, β = 92.01(2)°, Vm = 208.97(6) cm3/mol, R = 0.056, Rw = 0.034; Cs2[Lu3(CH3COO)10(OH)(H2O)]: monoclinic, C2/c (no.15), Z = 4, a = 2 138.5(6), b = 1 378.0(3), C = 1 482.9(4) pm, β = 106.15(2)°, Vm = 632.0(3) cm3/mol, R = 0.049, Rw = 0.036) were determined from four-circle-diffractometer data. The structures consist of dimers and trimers, respectively, that are built by bridging acetate groups. These units are fragments of the infinite chains of the Ho(CH3COO)3 type of structure. The isotypic compounds CsM(CH3COO)4 with M=Eu—Lu were synthesized and characterized by the X-ray Guinier technique. The thermal decomposition of CsLu(CH3COO)4 was examined with thermoanalytical methods (TG/DSC with coupled gas analysis) and the Guinier-Simon technique: it decomposes at 260°C in an endothermic reaction to Lu2O3 and Cs2CO3.
    Notes: Die Verbindungen CsLu(CH3COO)4 und Cs2[Lu3(CH3COO)10(OH)(H2O)] konnten aus wäßriger Lösung von Cs(CH3COO) und Lu(CH3COO)10 (OH)(H2O) dargestellt werden. Ihre Kristallstrukturen (CsLu(CH3COO)4: monoklin, P21/n (Nr. 14), Z = 8, a = 1293,1(2), b = 1323,8(2), c = 1 622,5(3) pm, β = 92,01(2)°, Vm = 208,97(6) cm3/mol, R = 0,056, Rw = 0,034; Cs2[Lu3(CH3COO)10(OH)(H2O)]: monoklin, C2/c (Nr. 15), Z = 4, a = 2138,5(6), b = 1378,0(3), C = 1 482,9(4) pm, β = 106,15(2)°, Vm = 632,0(3) cm3/mol, R = 0,049, Rw = 0,036) wurden anhand von Vierkreisdiffraktometerdaten bestimmt. In den Kristallstrukturen liegen zwei- bzw. dreikernige Baueinheiten vor, die durch verbrückende Acetatgruppen aufgebaut werden und Fragmente der unendlichen Ketten im Ho(CH3COO)3-Typ darstellen. Die isotypen Verbindungen CsM(CH3COO)4, M=Eu—Lu, wurden hergestellt und mittels Pulver-Röntgenmethoden charakterisiert. Das thermische Verhalten von CsLu(CH3COO)4 wurde mittels TG/DSC und simultaner Gasanalyse (EGA) einerseits und mit Hilfe der Guinier-Simon-Technik andererseits untersucht: Es zersetzt sich ab 260°C in Cs2CO3 und Lu2O3.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
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  • 3
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 1609-1615 
    ISSN: 0044-2313
    Keywords: Holmium(III) acetate ; Lutetium(III) acetate ; Synthesis ; Crystal Structure ; Thermal Behaviour ; Phase Transition ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Anhydrous Rare-Earth Acetates, M(CH3COO)3 (M = Sm—Lu, Y) with Chain Structures. Crystal Structures of Lu(CH3COO)3 and Ho(CH3COO)3Single crystals of the anhydrous rare-earth acetates containing lutetium (type 1) and holmium (type 2) were obtained by crystallisation at 120°C from diluted acetic acid solutions of their oxides and cesium acetate. The crystal structures [Lu(CH3COO)3: orthorhombic, a = 825.85(8), b = 1 398.1(2), c = 823.9(1) pm, Vm = 143.24(3) cm3/mol, space group Ccm21 (No. 36), Z = 4, R = 0.035, Rw = 0.030; Ho(CH3COO)3: monoclinic, a = 1 109.1(3), b = 2 916.3(10), c = 786.8(2) pm, β = 131.90(1)°, Vm = 142.58(8) cm3/mol, space group C2/c (No. 15), Z = 8, R = 0.039, Rw = 0.039, Rw = 0.026] were determined from four-circle diffractometer data sets. The structures consist of one-dimensional infinite chains built up by bridging acetate ions. Ho3+ is coordinated by 8 oxygen atoms, whereas Lu3+ has only 7 nearest oxygen neighbours. The chains are stacked parallel to the [001] direction. Isotypic compounds with Tm—Lu (type 1) and Sm—Er, Y (type 2) were prepared as powders and characterized by X-ray powder patterns. Thermoanalytical investigations (DTA, Guinier-Simon technique) of all compounds have shown that there is a first-order phase transition at 180°C (type 2) and in the range of 230-255°C (type 1). The high-temperature phase crystallizes with the known Sc(CH3COO)3 structure (type 0) where the rare earth cations are surrounded by 6 oxygen atoms. In the case of the type 1 compounds the phase transition is reversible.
    Notes: Einkristalle der wasserfreien Seltenerd-Acetate mit Lutetium (Typ 1) und Holmium (Typ 2) wurden aus den verdünnt essigsauren Lösungen ihrer Oxide durch Aussalzen mit Caesiumacetat bei ca. 120°C erhalten. Die Kristallstrukturen [Lu(CH3COO)3: orthorhombisch, a = 825,85(8), b = 1 398,1(2), c = 823,9(1) pm, Vm = 143,24(3) cm3/mol, Raumgruppe Ccm21 (Nr. 36), Z = 4, R = 0,035, Rw = 0,030; Ho(CH3COO)3: monoklin, a = 1 109,1(3), b = 2 916,3(10), c = 786,8(2) pm, β = 131,90(1)°, Vm = 142,58(8) cm3/mol, Raumgruppe C2/c (Nr. 15), Z = 8, R = 0,039, Rw = 0,026] wurden anhand von Intensitätsdatensätzen (Vierkreisdiffraktometer) bestimmt. Die Strukturen bestehen aus eindimensional-unendlichen acetatverbrückten Ketten, in denen Ho3+ von 8 Sauerstoffatomen umgeben ist, während Lu3+ nur 7 nächste Sauerstoffnachbarn hat. Die Acetatstränge, ∞1[M(CH3COO)3], verlaufen in Richtung [001] und sind im Falle von Lu(CH3COO)3 gleich einer „hexagonal-dichtesten Stabpackung“ angeordnet. Die zu beiden Verbindungen jeweils isotypen Acetate mit Tm—Lu (Typ 1) und mit Sm—Er, Y (Typ 2) konnten als Pulver hergestellt und mit Hilfe von Röntgen-Aufnahmen charakterisiert werden. Thermoanalytische Untersuchungen ergaben, daß die Verbindungen beider Strukturtypen bei erhöhter Temperatur (150-250°C) eine Phasenumwandlung 1. Art in die bekannte Sc(CH3COO)3-Struktur (Typ 0) durchlaufen, wobei sich die Koordinationszahlen von M3+ auf 6 erniedrigen. Im Falle der Acetate des Typs 1 ist die Phasenumwandlung reversibel.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
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