Library

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    Electronic Resource
    Electronic Resource
    Notes on the pollination mechanisms ofMoraea inclinata andM. brevistyla (Iridaceae) (1989)
    Springer
    Plant systematics and evolution 163 (1989), S. 201-209 
    Details
    ISSN: 1615-6110
    Keywords: Angiosperms ; Iridaceae ; Moraea inclinata ; M. brevistyla ; Bees ; Anthophoridae ; Halictidae ; Pollination mechanism ; flower morphology
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract Individual flowers ofMoraea inclinata are nectariferous and last about six hours. They appear to be pollinated largely by bees in the familyHalictidae (Lasioglossum spp.,Nomia spp.,Zonalictus) and to a lesser extent by bees in the familyAnthophoridae (Amegilla). The mechanism of bee-pollination inM. inclinata is the “Iris type”; i.e., each flower consists of three pollination units (an outer tepal, a partly exserted anther, and the opposed style branch which terminates in a pair of petal-like crests). Bees rarely visit more than one pollination unit per flower. Transferral of pollen to the bee is passive and nototribic although all bees collected on the flowers were female and 55% of the bees carried pollen loads with 2–5 pollen taxa in their scopae.Moraea brevistyla flowers are nectariferous but lack scent and last two days. They are visited infrequently by bees and only one femaleLasioglossum spec. carried the pollen ofM. brevistyla. Unlike flowers ofM. inclinata those ofM. brevistyla deposit pollen only on the head and thorax. Bee-mediated autogamy in both species is avoided due to the erratic foraging patterns of the bees and the flexibility of each stigma lobe as the bee backs out of the flower. Approximately 2–4 flowers in the inflorescences of both species (6–8 flowers/infloresence) develop into capsules.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00936515
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    The pollination biology ofHibbertia stricta (Dilleniaceae) (1984)
    Springer
    Plant systematics and evolution 147 (1984), S. 267-277 
    Details
    ISSN: 1615-6110
    Keywords: Angiosperms ; Magnoliidae ; Dilleniaceae ; Hibbertia stricta ; Lasioglossum (Halictidae) ; Pollination ecology ; melittophily ; pollen flowers ; Solanum Type flowers
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract The exines of pollen grains ofHibbertia stricta (DC.)R. Br. exF. Muell. (Sect.Pleurandra) wear an oily, yellow pollen coat that stains positively for lipids. The pollen is collected by asocial bees, exclusively. The most common floral foragers are members of the genusLasioglossum (subgenusChilalictus;Halictidae) and they harvest pollen via thoracic vibration. As these bees cling to the inflated anthers their pollen smeared bodies come in contact with either of the two wet, nonpapillate stigmas. The stigmas respond positively to cytochemical tests for the presence of esterase immediately following expansion of the corolla, indicating the effective pollination period. The foraging patterns of the bees are narrowly to broadly polylectic. AsH. stricta flowers are nectarless, it is not surprising that bees bearing mixed pollen loads always carry the pollen of at least one nectariferous, coblooming plant. The pollination biology ofH. stricta is compared with otherHibbertia spp. and with “pollen flowers” in general.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00989388
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Bee-pollination inHibbertia fasciculata (Dilleniaceae) (1986)
    Springer
    Plant systematics and evolution 152 (1986), S. 231-241 
    Details
    ISSN: 1615-6110
    Keywords: Angiosperms ; Dilleniaceae ; Hibbertia fasciculata ; Lasioglossum (Halictidae) ; Leioproctus (Colletidae) ; Myrtaceae ; Bees ; beetles ; floral symmetry ; stamens ; stigmas
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract In direct contrast to mostHibbertia spp., the flowers ofH. fasciculata R. Br. ex D. C. bear only a single whorl of stamens and these stamens are arranged separately (not in typical “bundles”). The short filaments are appressed to the three carpels so that the inflated, porose and introrsive anthers form a centralized cluster obscuring the three ovaries. The three slender styles emerge at right angles from between the filaments. These styles curve upward and the stigmas form the three points of a triangle; each stigma is approximately one millimeter outside the centralized cluster of anthers. The flowers are nectarless and bear a bright yellow corolla. A pungent and unpleasant fragrance appears to be concentrated within the pollenkitt. When native bees attempt to forage for the pollen, within the cluster of anthers, the ventrally deposited loads of pollen, on the bees' abdomens, contact the outer triangle of stigmas. The major pollinators ofH. fasciculata are female bees in the polylectic genera,Lasioglossum (subgenusChilalictus, Halictidae) andLeioproctus (Colletidae). These bees carry an average of more than two pollen taxa when they are caught foraging onH. fasciculata. 78% of the 47 bees, captured onH. fasciculata carried the pollen from at least one sympatric taxon bearing nectariferous flowers (e.g., genera in theMyrtaceae, Compositae, andEpacridaceae). The pollination biology ofH. fasciculata is assessed in relation to the known radiation of bee-pollinated flowers in the genusHibbertia, and within theDilleniaceae s. l.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00989430
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Self-isolation and insect pollination in the primitive angiosperms: New evaluations of older hypotheses (1987)
    Springer
    Plant systematics and evolution 156 (1987), S. 159-176 
    Details
    ISSN: 1615-6110
    Keywords: Arecales ; Cyclanthales ; Dilleniaceae ; Magnoliidae ; Angiosperm evolution ; bees ; beetles ; dichogamy ; dicliny ; insects ; protandry ; protogyny
    Source: Springer Online Journal Archives 1860-2000
    Topics: Biology
    Notes: Abstract A review of the literature, compiled over the past 40 years suggests new directions for theories discussing the evolution of reproductive isolation and entomophily in angiosperms. Data on breeding systems suggests that the protoangiosperms may have developed gametophytic self-incompatibility. Protogyny is probably ancestral to protandry and herkogamy. Although the proto-flowers were bisexual wide variation in the number of sexual organs within proto-flowers probably led to labile sexuality and early trends towards dicliny. Beetle-pollination in extant relicts appears too specialized to represent an ancestral condition. Rather, the proto-flowers may have been generalist entomophiles incorporating some beetles,Plecoptera, thrips, micropterigid moths and proto-dipterans into their fluctuating spectra of opportunistic pollinators. Bee-pollination is probably polyphyletic in origin evolving repeatedly from angiosperms showing these generalist syndromes. There is still no correlation between primitive bees (especiallyColletidae) and the relictual angiosperms. Pollen that is usually retained within the anthers following dehiscence and the presence of staminal filaments and styles characterizes most of the flowers of those relictual angiosperms pollinated by specialized, modernApoidea.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF00936071
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Das erste gemischt-valente Oxocobaltat(I, II): Rb5Co2O4 [1] (1993)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 540-550 
    Details
    ISSN: 0044-2313
    Keywords: Mixed-valent oxide of cobalt ; structure ; MAPLE, CHARDI, MEFIR-FIT ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: A New Mixed-Valent Oxide of Cobalt(I, II): Rb5Co2O4For the first time we obtained a new mixed-valent oxide of mono- and divalent Cobalt. Black-red single-crystals of Rb5Co2O4 were prepared by heating powders of “Rb6CdO4” in closed Co-cylinders at 500° during 48 days.Structure solution and refinement are covered by two measurements with four-circle diffractometers. MoKα: 2 145 Io(hkl), out of 2 818 Io(hkl), R = 9.85%, Rw = 5.93% AgKα: 1 813 Io(hkl) out of 4 007 Io(hkl), R = 9.46%, Rw = 6.51%) and confirm the space-group P1. The lattice constants are a = 696.4(1) pm, b = 922.2(3) pm, c = 958.9(3) pm, α = 117.99(2)°, β = 89.96(2)°, γ h= 108.12(2)°, Z = 2According to its composition Rb10[OCoO]2[OCoO2CoO] the structure is built up by two Co atoms of chemically and crystallographically different nature. We find isolated dumb-bell-like anions [O—Co—O]3- being already known with monovalent Co (e. g. K3CoO2) together with units [OCoO2CoO]4- of two connected triangles CoO3 being well-known from K2BeO2 ≜ K4[Be2O4]. ECoN/mEFIR calculations are made starting with values obtained by a new procedure called “MEFIR-FIT”.
    Notes: Durch 48tägiges Tempern von Rb6CdO4 in verschlossenen Co-Zylindern bei 500°C wurde erstmals ein gemischt-valentes Oxid des ein- und zweiwertigen Cobalts in Form von schwarzroten Einkristallen dargestellt. Die Strukturaufklärung mittels Vierkreisdiffraktometer (zwei Messungen: MoKα: 2 145 von 2 818 Io(hkl), R = 9,85%, Rw = 5,93% AgKα: 1 813 von 4 007 Io(hkl), R = 9,46%, Rw = 6,51%) belegt die Raumgruppe P1. Die Gitterkonstanten nach Pulverdaten sind a = 696,4(1) pm, b = 922,2(3) pm, c = 958,9(3) pm, α = 117,99(2)°, β = 89,96(2)°, γ = 108,12(2)°, Z = 2 (Standardabweichungen in Einheiten der letzten Stelle Klammern).Die chemisch unterschiedlichen Co-Teilchen nehmen auch kristallographisch unterschiedliche Umgebungen an: Während CoI in Form „isolierter“, linearer Hanteln [O—Co—O]3- vorliegt, bildet CoII[Co2O4]4--Einheiten in Form zweier kantenverknüpfter Dreiecke CoO3, analog dem Aufbau des Anions in K4[Be2O4] [2].Zur Berechnung der Startwerte der „Mittleren Fiktiven Ionenradien“ (MEFIR) wird ein neues Verfahren (MEFIR-FIT) angewandt.
    Additional Material: 12 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19936190320
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    K10[Co4O9], ein neues Oxocobaltat(II) mit oligomerem Anion (1993)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 1807-1817 
    Details
    ISSN: 0044-2313
    Keywords: New oligooxocobaltate(II) ; structure ; MAPLE ; CHARDI ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: K10[Co4O9], a New Oligooxocobaltate(II)For the first time dark-red single crystals of K10[Co4O9] were obtained by heating mixtures of KO0.48 and CdO (molar ratio 2.7:1) in closed Co-cylinders at 450°C during 73 d.Structure solution and refinement (four-circle diffractometer data, Mo Kα, 2 996 out of 2 996 Io(hkl), R = 5.20%, Rw = 3.03%) confirm the space-group P1 and show structural relationship with Na10[Co4O9] [2]. The lattice constants are a = 667.84(5) pm, b = 917.91(9) pm, c = 908.49(7) pm, α = 119.400(7)°, β = 90.851(7)°, γ = 110.260(6)°, Z = 1. (powder data (Guinier-Simon), standard deviations in parentheses)MAPLE calculations are made and a comparative survey of MAPLE values of oxocobaltates(II) is given.
    Notes: Erstmals wurde K10[Co4O9] in Form dunkelroter Einkristalle durch „Reaktion mit der Gefäßwand“ beim Tempern inniger Gemenge von KO0,48 mit CdO (molares Verhältnis 2,7:1, 73 d, 450°C) in verschlossenen Co-Bomben dargestellt.Die Strukturaufklärung mittels Vierkreisdiffraktometer (Mo Kα, 2 996 von 2 996 Io(hkl), R = 5,20%, Rw = 3,03%) bestätigt die strukturelle Analogie zu Na10[Co4O9] [2].K10[Co4O9] kristallisiert triklin (Raumgruppe P1) mit a = 667,84(5) pm, b = 917,91(9) pm, c = 908,49(7) pm, α = 119,400(7)°, β = 90,851(7)°, γ = 110,260(6)°, Z = 1. (Guinier-Simon-Daten, Standardabweichungen in Klammern)Der Madelunganteil der Gitterenergie, MAPLE, wird berechnet und mit Werten bereits bekannter Oxocobaltate(II) verglichen.
    Additional Material: 9 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19936191102
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Das erste quaternäre Oxocobaltat(I): CsK2[CoO2] (1994)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 187-191 
    Details
    ISSN: 0044-2313
    Keywords: Oxide of monovalent cobalt ; structure ; magnetism ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The First Quaternary Oxide of Monovalent Cobalt: CsK2[CoO2]Dark-red single crystals of CsK2[CoO2] were obtained via „reaction with the cyliner surface“ by heating powders of Cs2K2Cd3O5 in closed Co-cylinders at 500°C during 48 d.Structure solution and refinement (four-circle diffractometer data, MoKα, 147 independent Io(hkl), none was omitted, R = 3.42%, Rw = 2.24%) show close relationship with RbNa2[NiO2] [2].The lattice-constants are: \documentclass{article}\pagestyle{empty}\begin{document}$$ a{\rm = 529.506(5) pm, }c{\rm = 986.18(1) pm, }Z{\rm = 2}{\rm .} $$\end{document} (powder data, standard deviations in parentheses) MAPLE calculations, investigations of magnetism and EPR measurement add to the monovalence of Co.
    Notes: Tiefdunkelrote Einkristalle von CsK2[CoO2] entstanden durch „Reaktion mit der Gefäßwand“ von vorgetempertem Cs2K2Cd3O5 in verschlossenen Co-Bomben bei 500°C während 48 d.Die Strukturaufklärung mittels Vierkreisdiffraktometer (MoKα, alle 147 symmetrieunabhängigen Io(hkl) zur Verfeinerung, R = 3,42%, Rw = 2,24%) belegt die strukturelle Analogie zu RbNa2[NiO2] [2], dem ersten quaternären Oxoniccolat(I) der Alkalimetalle.Die Gitterkonstanten nach Pulverdaten (Guinier-Simon) betragen: \documentclass{article}\pagestyle{empty}\begin{document}$$ a{\rm = 529,506(5) pm,}c{\rm = 986,18(1) pm,}Z{\rm = 2}{\rm .} $$\end{document} (Standardabweichungen in Einheiten der letzten Stelle in Klammern)MAPLE-Berechnungen, magnetische Untersuchungen und EPR-Messungen belegen erstmals die Anwesenheit formal einwertigen Cobalts in einem Oxid.
    Additional Material: 6 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19946200202
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Über Oxide mit dem “Butterfly-Motiv”: Rb6[Fe2O5] und K6[Fe2O5] (1992)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 618 (1992), S. 63-73 
    Details
    ISSN: 0044-2313
    Keywords: New oxides of divalent iron ; structure ; MAPLE ; CHARDI ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: New Oxides with the “Butterfly-Motive”: Rb6[Fe2O5] and K6[Fe2O5]Rb6[Fe2O5] and K6[Fe2O5] were obtained for the first time by annealing intimate mixtures of “Rb6CdO4” with CdO (molar ratio 1 : 1.1) and KO0.48 with CdO (molar ratio 5.9 : 1) respectively in closed Fe-cylinders. Determination and refinement of the crystalstructure confirms the space group C2/m (four-circle-diffractometer data). Rb6[Fe2O5]: Ag Kα, 720 out of 1220 Io(hkl), R = 9.68%, Rw = 6.09%; a = 718.9pm, b = 1183.1 pm, c = 695.4pm, β = 95.05°, Z = 2; K6[Fe2O5]: MoKα, 1214 Out of 12141o(hkl), R = 3.20070, Rw = 2.48%, a = 691.21 pm, b = 1142.78pm, c = 665.50pm, β = 93.82°, Z = 2. The binuclear unit [O2FeOFeO2]6- already known to be planar with oxoferrates(II) now was observed to be angular here and closely related to Na6[Be2O5].
    Notes: Rb6[Fe2O5] und K6[Fe2O5] wurden erstmals durch Tempern inniger Gemenge von “Rb6CdO4” mit CdO (im Verhältnis 1 : 1,1) bzw. KO0,48 mit CdO (im Verhältnis 5,9 : 1) in verschlossenen Fe-Zylindern in Form von roten Einkristallen erhalten. Die Strukturaufklärung (Vierkreisdiffraktometerdaten, Rb6[Fe2O5]: Ag Kα, 720 von 1 220 Io(hkl), R = 9,68%, Rw = 6,09%; K6[Fe2O5]: Mo Kα, 1 214 von 1 214 Io(hkl), R = 3,20%, Rw = 2,48%) belegt die Raumgruppe C2/m. Rb6[Fe2O5]: a = 718,9 pm, b = 1183,1 pm, c = 695,4 pm, β = 95,05°, Z = 2. K6[Fe2O5]: a = 691,21 pm, b = 1 142,78 pm, c = 665,50 pm, β = 93,82°, Z = 2. Zum ersten Male wird bei derartigen Ferraten eine deutlich gewinkelte Baueinheit [Fe2O5]6- beobachtet, wie sie analog bei Na6[Be2O5] vorliegt.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19926180112
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    Zur Existenz polynärer Oxide der Alkalimetalle mit einwertigen Cobalt bzw. Nickel [1, 2] (1993)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 923-933 
    Details
    ISSN: 0044-2313
    Keywords: Oxides of monovalent Co and Ni ; structure ; MAPLE ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: On the Existence of Polynary Oxides of the Alkali Metals with Monovalent Cobalt and NickelFor the first time we obtained RbNa2NiO2, KNa2NiO2, Na3CoO2 and K3CoO2 [RbNa2NiO2: Na2NiO2 + Rb2O, Rb:Ni = 1.8:1, 600°C, 28 d, Ni-tube; KNa2NiO2: Na2NiO2 + K2O, K:Ni = 1.8:1, 600°C, 20 d, Ni-tube; Na3CoO2: Na2O + CoO: Na:Co = 8.8:1, 500°C, 20 d, Co-tube; K3CoO2: K2O + CoO: K:Co = 4.4:1, 550°C, 20 d, Co-tube]. According to X-ray structure analysis of single crystals monovalent Co and Ni is present [always four-circle-diffractometer data, MoKα-radiation; RbNa2NiO2: AED 2, all 163 Io(hkl), R = 3.4%, Rw = 1.9%, I4/mmm, a = 461.7(1), c = 973.6(3) pm, Z = 2; KNa2NiO2: AED 2, all 341 Io(hkl), R = 5.6%, Rw = 3.5%, Cmma, a = 1 048.5(3), b = 626.8(1), c = 621.9(1) pm, Z = 4; Na3CoO2: PW 1 100, 517 of 568 Io(hkl), R = 2.9%, Rw = 1.8%, P42/mnm, a = 940.0, c = 464.5 pm, Z = 4; K3CoO2: PW 1 100, all 940 Io(hkl), R = 5.0%, Rw = 3.9%, Pnma, a = 1 190.0, b = 730.4, c = 604.1 pm, Z = 4]. All samples are red, the single crystals transparent. Two O2- coordinate Ni1+ and Co1+, respectively, like a dumb-bell. Mean Fictive Ionic Radii, MEFIR, and Effective Coordination Numbers, ECoN, and Madelung part of lattice energy, MAPLE, are given.
    Notes: Erstmals wurden RbNa2NiO2, KNa2NiO2, Na3CoO2 und K3CoO2 dargestellt [RbNa2NiO2: Na2NiO2 + Rb2O, Rb:Ni = 1,8:1, 600°C, 20 d, Nickelbombe; KNa2NiO2: Na2NiO2 + K2O, K:Ni = 1,8:1, 600°C, 20 d, Nickelbombe; Na3CoO2: Na2O + CoO, Na:Co = 8,8:1, 500°C, 20 d, Cobaltbombe; K3CoO2: K2O + CoO, K:Co = 4,4:1, 550°C, 20 d, Cobaltbombe]. Nach Einkristalldaten weisen Cobalt wie Nickel die Oxydationsstufe + 1 auf [jeweils Vierkreisdiffraktometer mit MoKα-Strahlung; RbNa2NiO2: AED 2, alle 163 Io(hkl), R = 3,4%, Rw = 1,9%, I4/mmm, a = 461,7(1), c = 973,6(3) pm, Z = 2; KNa2NiO2: AED 2, alle 341 Io(hkl), R = 5,6%, Rw = 3,5%, Cmma, a = 1 048,5(3), b = 626,8(1), c = 621,9(1) pm, Z = 4; Na3CoO2: PW 1 100, 517 aus 568 Io(hkl), R = 2,9%, Rw = 1,8%, P42/mnm, a = 940,0, c = 464,5 pm, Z = 4; K3CoO2: PW 1 100, alle 940 Io(hkl), R = 5,0%, Rw = 3,9%, Pnma, a = 1 190,0, b = 730,4, c = 604,1 pm, Z = 4].Alle Präparate sind rot, die Einkristalle transparent. Ni1+ bzw. Co1+ ist jeweils in Form einer Hantel von 2 O2- koordiniert. Mittlere Fiktive Ionenradien (MEFIR) und Effektive Koordinationszahlen (ECoN), sowie der Madelunganteil der Gitterenergie (MAPLE), werden angegeben.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19936190520
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    Das erste Oxoferrat(I): Zur Konstitution von K3[FeO2] und K3[NiO2] (1993)
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 969-975 
    Details
    ISSN: 0044-2313
    Keywords: Oxide of monovalent Fe and Ni ; preparation ; structure ; MAPLE comparisons ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: The First Oxoferrate(I): On the Constitution of K3[FeO2] and K3[NiO2]Garnet-red single crystals of K3[FeO2] were obtained for the first time by heating intimate mixtures of K6[CdO4] and CdO (molar ratio 1:1.16) in closed Fe-cylinders at 450°C during 40 d.The same way of preparation via “reaction with the cylinder surface” was applied to prepare similarly coloured single crystals of K3[NiO2] (K6CdO4 in closed Ni-cylinders at 500°C during 49 d).The structure determination by four circle diffractometer data (MoKα, K3[FeO2]: 731 out of 731 Io(hkl), R = 5.76%, Rw = 5.33%, K3[NiO2]: 755 out of 755 Io(hkl), R = 8.70%, Rw = 4.25%) confirms the space groups P 41212 and P 43212, respectively.K3[FeO2]: a = 604.2(2) pm, c = 1 402.7(3) pm, Z = 4K3[NiO2]: a = 603.6(1) pm, c = 1 405.2(2) pm, Z = 4.(powder data, standard deviations in parentheses)Essential feature of the structure are the dumb-bell-like anions [O—M—O]3- (M = Fe, Ni). Their arrangement corresponds to a stuffed derivative of the KrF2-type. Magnetic properties of K3[FeO2] were determined and cover the monovalence of Fe. MAPLE-calculations reveal the strong coincidence of monovalent VIIIb-cations.
    Notes: K3[FeO2] wurde erstmals in Form granatroter Einkristalle durch 40tägiges Tempern von K6CdO4 und CdO (molares Verhältnis vor dem Verreiben 1:1,16) in verschlossenen Fe-Zylindern bei 450°C dargestellt. Ebenfalls durch „Reaktion mit der Gefäßwand“ wurden isotype, gleichfarbene Einkristalle von K3[NiO2] durch Tempern von K6CdO4 (500°C, 49 d) in verschlossenen Ni-Zylindern erhalten. Die Strukturaufklärung mittels Vierkreisdiffraktometer (K3[FeO2]: MoKα, 731 von 731 Io(hkl), R = 5,76%, Rw = 5,33%, K3[NiO2]: MoKα, 755 von 755 Io(hkl), R = 8,70%, Rw = 4,25%.) verweist auf die beiden zueinander enantiomorphen Raumgruppe P 41212 bzw. P 43212.Die Gitterkonstanten nach Pulverdaten (Guinier-Simon) betragen für K3[FeO2]: a = 604,2(2) pm, c = 1 402,7(3) pm, Z = 4 für K3[NiO2]: a = 603,6(1) pm, c = 1 405,2(2) pm, Z = 4.(Standardabweichungen jew. in Einheiten der letzten Stelle in Klammern.)Die Struktur läßt sich als „aufgefüllte“ KrF2-Variante [2] beschreiben, bei der hantelförmige Anionen [FeO2]3- bzw. [NiO2]3- vorliegen.Die unerwartete Einwertigkeit von Eisen wird zusätzlich durch magnetische Messungen gestützt.Der Madelunganteil der Gitterenergie, MAPLE, wird für die ternären Oxide berechnet und daraus ein Schätzwert für die binären Oxide Fe2O und Ni2O angegeben.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1002/zaac.19936190602
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...