ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

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
    s.l. : American Chemical Society
    Journal of the American Chemical Society 113 (1991), S. 794-801 
    ISSN: 1520-5126
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    Oxford, UK : Blackwell Publishing Ltd
    Annals of the New York Academy of Sciences 684 (1993), S. 0 
    ISSN: 1749-6632
    Source: Blackwell Publishing Journal Backfiles 1879-2005
    Topics: Natural Sciences in General
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 3
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Hexaminecyclotriphosphazenehemiammoniate, P3N3(NH2)6 · 0.5 NH3, a Product of High Pressure Ammonolysis of White PhosphorusWhite phosphorus gives at NH3-pressures ≥5 kbar and temperatures above 250°C in a disproportionation reaction P3N3(NH2)6 · 0.5 NH3; besides these products red phosphorus is formed. The yield on P3N3(NH2)6 · 0.5 NH3 increases with T and is about 70-80% at 400°C as to the disproportionation reaction of the amount of white phosphorus.X-ray structure determination was successful on single crystals of P3N3(NH2)6 · 0.5 NH3. Pbca, N = 8 a = 11.395(3) Å, b = 12.935(4) Å, c = 12.834(4) Å R = 0.035, Rw = 0.041 with w = 1, N (Fo2) ≥ 3σ(Fo2) = 1371, N(Var.) = 166.The molecules are connected by N—H—N-bridgebonds with 3.04 Å ≤ d(N … N) ≤ 3,19 Å and d(N—H) = 0.87 Å. The compound is furthermore characterized by IR-data and its thermical behaviour.
    Notes: Bei NH3-Drücken ≥5 kbar und Temperaturen oberhalb 250°C disproportioniert weißer Phosphor zu P3N3(NH2)3 · 0,5 NH3 und PH3; daneben entsteht roter Phosphor. Die Ausbeute an P3N3(NH2)6 · 0,5 NH3 steigt mit T; sie beträgt bei 400°C etwa 70-80%, bezogen auf die Disproportionierungsreaktiondes eingesetzten Phosphors.An Einkristallen von P3N3(NH2)6 · 0,5 NH3 wurde röntgenographisch die Struktur bestimmt Pbca, Z = 8 a = 11,395(3) Å, b = 12,935(4) Å, c = 12,834(4) Å R = 0,035, Rw = 0,041 mit w = 1 Z(Fo2) = 1317, Z(Var.) = 166.Die Moleküle sind untereinander durch N—H--·N-Brückenbindungen mit 3,04 Å ≤ d(N … N) ≤ 3,19 Å bei d(N—H) = 0,87 Å verknüpft. Weiterhin wird die Verbindung durch IR-Daten und ihr thermisches Verhalten charakterisiert.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 584 (1990), S. 129-137 
    ISSN: 0044-2313
    Keywords: Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Preparation and Crystal Structure of a Potassium Imidenitridesilicate, K3Si6N5(NH)6Crystals of K3Si6N5(NH)6 sufficient for an X-ray structure determination are formed when potassium and silicium react with supercritical ammonia under the following conditions K:Si = 1:1, P(NH)3 = 6 kbar, T = 500°C within 3 days in a temperature gradient within the autoclaves used. The compound crystallizes cubic with a = 10.789(4) Å, the space group is P4332 (with tests for enantiomorphous pairs) and the cell contains four formula units. The positions of H-atoms are determined. The following data characterize the structure determination: N(F02) = 518 with 517 ≥ 3σ(F02) N(Variables) = 37, R = 0.019 resp. Rw = 0.017.The conditions for the synthesis of the compound and its structure are discussed with respect to Si3N4 and Si2N2(NH).
    Notes: Für eine röntgenographische Strukturbestimmung ausreichend große Kristalle von K3Si6N5(NH)6 bilden sich bei der Umsetzung von Kalium und Silicium in überkritischem Ammoniak bei K:Si = 1:1, P(NH3) = 6 kbar, T = 500°C und 3d Reaktionszeit im Temperaturgefälle der eingesetzten Autoklaven. Die Verbindung kristallisiert kubisch mit a = 10,789(4)Å in der Raumgruppe P4332 (nach Enantiomerentests) mit vier Formeleinheiten. Die Lagen der H-Atome konnten eindeutig ermittelt werden. Folgende Daten charakterisieren die Strukturbestimmung: Z(F02) = 518; davon sind 517 ≥ 3σ(F02); Z(Variable) = 37, R = 0,019 bzw. Rw = 0,017.Die Darstellungsbedingungen der Verbindung und ihre Struktur werden im Hinblick auf Si3N4 und Si2N2(NH) diskutiert.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 5
    ISSN: 0044-2313
    Keywords: Sodium hydroxide monohydrate ; monodeuterate ; crystal structure ; neutron diffraction ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Unusual H-Bonds in Sodium Hydroxide Monohydrate: X-Ray and Neutron Diffraction on NaOH · H2O and NaOD · D2O, respectivelyX-ray data revealed the structure of NaOH · H2O including the H positions. Neutron diffraction on microcrystalline NaOD · D2O was used for comparison of H with D positions: \documentclass{article}\pagestyle{empty}\begin{document}$$ \begin{array}{l}{\rm NaOH} \cdot {\rm H}_2 {\rm O}:{\rm Pbca},\,{\rm Z} = 8,\,{\rm a} = 11.825(2){\rm {\AA}},\,{\rm b} = 6.213(2){\rm {\AA}},\,{\rm c} = 6.069(2){\rm {\AA}}\\{\rm Z}({\rm F}_\circ)\,{\rm mit}\,({\rm F}_\circ)^2 \ge 1{\rm \sigma}({\rm F}_\circ)^2 = 635,\,{\rm Z}\,({\rm Parameter}) = 40,\,{\rm R}/{\rm R}_{\rm w} = 0.022/0.024\\{\rm NaOD} \cdot {\rm D}_2 {\rm O}:{\rm \lambda} = 2.016{\rm {\AA}},\,10^\circ \le 2\Theta \le 86^\circ,\,{\rm R} = 0.049\,({\rm nur}\,{\rm D - Lagen variiert})\\\end{array} $$\end{document}The compound crystallizes in a layer-type structure with the sequence … /O Na O O Na O/ … closely related to that of hydrargillite Al(OH)3 with … /O 2/3 Al O O 2/3 Al O/ …. Between OH- ions as acceptors and H2O molecules mäandric, one-dimensional infinite strong H-bonds occur with d(O…O) = 2.66 Å and 2.69 Å. These lie within O-layers that coordinate Na+ ions. Bridge-bonds between OH- ions as donors and H2O molecules as acceptors connect the /O Na O/-layers with d(O…O) = 3.18 Å.
    Notes: An NaOH · H2O wurde röntgenographisch die Atomanordnung einschließlich der H-Lagen bestimmt und Neutronenbeugungsmessungen an feinkristallinem NaOD · D2O vergleichend ausgewertet: \documentclass{article}\pagestyle{empty}\begin{document}$$ \begin{array}{l}{\rm NaOH} \cdot {\rm H}_2 {\rm O}:{\rm Pbca},\,{\rm Z} = 8,\,{\rm a} = 11,825(2){\rm {\AA}},\,{\rm b} = 6,213(2){\rm {\AA}},\,{\rm c} = 6,069(2){\rm {\AA}}\\{\rm Z}({\rm F}_\circ)\,{\rm mit}\,({\rm F}_\circ)^2 \ge 1{\rm \sigma}({\rm F}_\circ)^2 = 635,\,{\rm Z}\,({\rm Parameter}) = 40,\,{\rm R}/{\rm R}_{\rm w} = 0,022/0,024\\{\rm NaOD} \cdot {\rm D}_2 {\rm O}:{\rm \lambda} = 2,016{\rm {\AA}},\,10^\circ \le 2\Theta \le 86^\circ,\,{\rm R} = 0,049\,({\rm nur}\,{\rm D - Lagen variiert})\\\end{array} $$\end{document}Die Verbindung kristallisiert in einer Schichtstruktur der Abfolge … /O Na O O Na O/ … verwandt zu der von Hydrargillit, Al(OH)3 mit … /O 2/3 Al O O 2/3 Al O/ …. Zwischen Hydroxidionen als Akzeptoren und H2O-Molekülen treten mäanderförmig eindimensional unendliche starke H-Brücken auf mit d(O…O) = 2,66 Å und 2,69 Å. Diese liegen in O-Schichten, die Na+-Ionen koordinieren. Weitere Brückenbindungen zwischen OH--Ionen als Donatoren und H2O-Molekülen als Akzeptoren verknüpfen die /O Na O/-Schichtpakete mit d(O…O) = 3,18 Å.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 6
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 619 (1993), S. 303-310 
    ISSN: 0044-2313
    Keywords: Potassium diamido dioxosilicate ; rubidium diamido dioxosilicate ; cesium diamido dioxosilicate ; crystal structures ; IR spectra ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Synthesis and Crystal Structure of Alkali Metal Diamido Dioxosilicates M2SiO2(NH2)2 with M ≙ K, Rb and CsSiO2 - α-quartz - reacts with alkali metal amides MNH2 (M ≙ K, Rb, and Cs) in molar ratios from 1:2 to 1:10 at 450°C ≤ T ≤ 600°C and P(NH3) = 6 kbar in autoclaves to diamidodioxosilicates M[SiO2(NH2)2]. Crystals of the colourless compounds which hydrolyze rapidly were investigated by x-ray methods. Following data characterize the structure determination on the isotypic compounds: The structures of the diamidodioxosilicates are closely related to the β—K2SO4 type. They contain isolated [SiO2(NH2)2]2- ions. K+ ions and hydrogen bridge bonds N—H…O (with 2.68 Å ≤ d(N…O) ≤ 2.78 Å for the K compound) connect the tetrahedral anions.
    Notes: SiO2 - α-Quarz - reagiert mit Alkalimetallamiden MNH2 (M ≙ K, Rb und Cs) im Molverhältnis 1:2 bis 1:10 bei 450°C ≙ T ≙ 600°C und P(NH3) = 6 kbar in Hochdruckautoklaven zu Diamidodioxosilicaten M2SiO2(NH2)2. Kristalle der farblosen, sehr hydrolyseempfindlichen Verbindungen wurden röntgenographisch untersucht. Folgende Daten charakterisieren die Strukturbestimmungen an den isotypen Verbindungen: Die Struktur der Diamidodioxosilicate ist eng verwandt mit dem β-K2SO4-Typ. Es liegen isolierte [SiO2(NH2)2]2--Ionen vor, die durch K+-Ionen und Wasserstoffbrückenbindungen N—H…O (mit 2,68 Å ≤ d(N…O) ≤ 2,78 Å für M ≙ K) verknüpft sind.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 7
    ISSN: 0044-2313
    Keywords: Potassium hexahydroxoscandate ; rubidium hexahydroxoscandate ; rubidium hexahydroxochromate ; structure determination ; crystal chemistry ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Structural Relationship of Potassium Hexahydroxoscandate(III), K3[Sc(OH)6] with the Isotypic Hydroxometallates Rb3[Sc(OH)6], K3[Cr(OH)6], and Rb3[Cr(OH)6]Ternary hydroxides M3I}MIII(OH)6{ with MI = K, Rb and MIII = Sc, Cr were obtained in the same way as K3[Cr(OH)6] [1] from alkali metal amides and d-metal nitrates by a comproportionation reaction of amide and nitrate ions in supercritical ammonia to elementary nitrogen and hydroxide ions at 523 K and 3 ≤ p(NH3) ≤ 6 kbar within 1 to 3 months. Their structures were determined by single crystal x-ray methods inclusive the positions of the hydrogen atoms. The ratio of size of r(MI)/r(MIII) is related to the symmetry of these hydroxometallates. Structural relationships between K3[Sc(OH)6] and Rb3[Sc(OH)6], K3(Cr(OH)6], Rb3[Cr(OH)6]) and K4[CdCl6] [4] are discussed.
    Notes: Ternäre Hydroxide M3I{MIII(OH)6}mit MI = K, Rb und MIII = Sc, Cr wurden analog zu K3[Cr(OH)6] [1] aus Alkalimetallamiden und d-Metallnitraten durch Komproportionierung von Amid- und Nitrationen zu elementarem Stickstoff und Hydroxidionen in überkritischem Ammoniak bei 523 K und 3 ≤ p(NH3) ≤ 6 kbar innerhalb von 1 bis 3 Monaten dargestellt. Die Atomanordnungen der Verbindungen wurden einschließlich der H-Positionen röntgenographisch an Einkristallen bestimmt. Das Größenverhältnis r(MI)/r(MIII) korreliert mit der Symmetrie dieser Verbindungen. Strukturchemische Beziehungen von K3[Sc(OH)6 zu Rb3[Sc(OH)6], K3[Cr(OH)6], Rb3[Cr(OH)6] zu K4[CdCl6] [4] werden diskutiert.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    Weinheim : Wiley-Blackwell
    Zeitschrift für anorganische Chemie 620 (1994), S. 965-968 
    ISSN: 0044-2313
    Keywords: Hexamine cyclotriposphazene ; crystal growth ; crystal structure ; hydrogen-bonding ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Crystal Structure of Hexamine Cyclotriphosphazene, P3N3(NH2)6In the presence of KNH2 hexamine cyclotriphosphazene semi ammoniate (molar ratio 12:1) in NH3 gives crystals of solvent free P3N3(NH2)6 within 5 d at 130°C and p(NH3) = 110 bar. The structure was solved by X-rax methods: P3N3(NH2)6: P21/c, Z = 4, a = 10.889(6) Å, b = 5.9531(6) Å, c = 13.744(8) Å, β = 97.83(3)°, Z(Fo) = 1 721 with (Fo)2 ≥ 3σ(Fo)2, Z(var.) = 157, R/Rw = 0,036/0,041The structure contains columns of molecules P3N3(NH2)6 all in the same orientation. The six-membered rings within one molecule have boat conformation. The columns are stacked together in a way that one is surrounded by four others shifted by half a lattice constant in direction [010]. Strong hydrogen bridge-bonds N—H…N connect molecules within the columns and between them.
    Notes: Bei Umsetzungen von Hexamincyclotriphosphazensemiammoniakat mit KNH2 (Molverhältnis 1:12, 5 d, T = 130°C, P(NH3) = 110 bar) in NH3 wurden Kristalle von ammoniakfreiem P3N3(NH2)6 als Nebenprodukt erhalten. Die Struktur dieser Verbindung wurde röntgenographisch bestimmt: P3N3(NH2)6: P21/c, Z = 4, a = 10,889(6) Å, b = 5,9531(6) Å, c = 13,744(8) Å, β = 97,83(3)°, Z(Fo) = 1 721 für (Fo)2 ≥ 3σ(Fo)2, Z(Parameter) = 157, R/Rw = 0,036/0,041In der Struktur liegen Säulen deckungsgleich gestapelter Moleküle P3N3(NH2)6 mit wannenförmiger Konformation vor. In nächster Umgebung befinden sich vier weitere Säulen, die um eine halbe Gitterkonstante in Richtung [010] entlang der Staperlrichtung gegenüber einer Bezugssäule versetzt sind. Starke Wasserstoffbrückenbidungen N—H⋅⋅⋅N verknüpfen die Moleküle sowohl zwischen den Säulen als auch in Säulenrichtung.
    Additional Material: 3 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 9
    ISSN: 0044-2313
    Keywords: Alkali metal hydrogensulfides ; preparation ; differential scanning calorimetry ; crystal structures ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Dynamical Behaviour of Linear Molecular Anions in the Hydrogensulfides of Sodium, Potassium and Rubidium: Differential Scanning Calorimetry, X-ray and Neutron DiffractionHydrogensulfides of the alkali metals M ≅ Na, K, Rb were prepared in autoclaves by the reaction of the corresponding metals with H2S and D2S, respectively, in the temperature range from 50°C to 150°C. Differential scanning calorimetry, X-ray and neutron diffraction methods reveal that both, the HS--and DS--compounds occur in three crystalline modifications with HT ≅ high-, MT ≅ medium- and LT ≅ low-temperature form: \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} {\rm HT\hspace{-3pt}: Fm3m, Z = 4} \\ \qquad{\rm NaDS\quad a = 6.056(5) }\mathop {\rm A}\limits^\circ {\rm \,\,at\,\, 433\, K} \\ \qquad{\rm KDS{\hphantom{a}}\quad a = 6.682(4) }\mathop {\rm A}\limits^\circ {\rm \,\,at\,\, 453\, K} \\ \qquad{\rm RbDS\quad a = 6.978(7)}\mathop {\rm A}\limits^\circ {\rm \,\,at\,\, 440\, K} \\ {\rm MT\hspace{-3pt}: R}\overline {\rm 3} {\rm, Z = 3} \\ \qquad{\rm NaDS \quad a = 4.499(5) }\mathop {\rm A}\limits^\circ {\rm,\, c = 9.177(5) }\mathop {\rm A}\limits^\circ {\rm \,\,at\,\, 298\, K} \\ \qquad{\rm RbDS \quad a = 5.188(8) }\mathop {\rm A}\limits^\circ {\rm,\, c = 10.285(9) }\mathop {\rm A}\limits^\circ {\rm \,\,at\,\, 298\, K} \\ {\rm TT\hspace{-3pt}: P2}_{\rm 1} {\rm /m, Z = 2} \\ \qquad{\rm NaDS \quad a = 3.911(1) }\mathop {\rm A}\limits^\circ {\rm,\, b = 4.447(1) }\mathop {\rm A}\limits^\circ {\rm,\, c = 5.930(2) }\mathop {\rm A}\limits^\circ,\,\beta {\rm = 99.55(2)}^\circ {\rm \,\,at\,\, 9\, K} \\ \qquad{\rm KDS{\hphantom{a}}\quad a = 4.309(2) }\mathop {\rm A}\limits^\circ {\rm,\, b = 4.908(2) }\mathop {\rm A}\limits^\circ {\rm,\, c = 6.544(3) }\mathop {\rm A}\limits^\circ,\,\beta {\rm = 100.83(3)}^\circ {\rm \,\,at\,\, 10\, K} \\ \qquad{\rm RbDS \quad a = 4.515(2) }\mathop {\rm A}\limits^\circ {\rm,\, b = 5.116(2) }\mathop {\rm A}\limits^\circ {\rm,\, c = 6.815(3) }\mathop {\rm A}\limits^\circ,\,\beta {\rm = 101.67(2)}^\circ {\rm \,\,at\,\, 10\, K} \\ \end{array}$$\end{document}$$\end{document} The temperatures and enthalpies for the changes of modifications of the H- and D-compounds are given and the atomic arrangements revealed mainly by neutron diffraction data are discussed, in relation to, for example, size of cations.
    Notes: Durch Umsetzung der Alkalimetalle M ≅ Na, K und Rb mit H2S bzw. D2S in Autoklaven bei Temperaturen zwischen 50°C und 150°C wurden die entsprechenden Hydrogensulfide MHS bzw. MDS dargestellt. Differential-Scanning-Kalorimetrie, Röntgen- und Neutronenbeugung belegen für die HS--bzw. DS--Verbindungen jeweils drei kristalline Modifikationen mit HT ≅ Hoch-, MT ≅ Mittel- und TT ≅ Tieftemperaturform: \documentclass{article}\pagestyle{empty}\begin{document}$$\begin{array}{l} {\rm HT\hspace{-3pt}: Fm3m, Z = 4} \\ \qquad{\rm NaDS\quad a = 6,056(5) }\mathop {\rm A}\limits^\circ {\rm \,\,{bei}\,\, 433\, K} \\ \qquad{\rm KDS{\hphantom{a}}\quad a = 6,682(4) }\mathop {\rm A}\limits^\circ {\rm \,\,{bei}\,\, 453\, K} \\ \qquad{\rm RbDS\quad a = 6,978(7)}\mathop {\rm A}\limits^\circ {\rm \,\,{bei}\,\, 440\, K} \\ {\rm MT\hspace{-3pt}: R}\overline {3} {\rm, Z = 3} \\ \qquad{\rm NaDS \quad a = 4,499(5) }\mathop {\rm A}\limits^\circ {\rm,\, c = 9,177(5) }\mathop {\rm A}\limits^\circ {\rm \,\,{bei}\,\, 298\, K} \\ \qquad{\rm RbDS \quad a = 5,188(8) }\mathop {\rm A}\limits^\circ {\rm,\, c = 10,285(9) }\mathop {\rm A}\limits^\circ {\rm \,\,{bei}\,\, 298\, K} \\ {\rm TT\hspace{-3pt}: P2}_{\rm 1} {\rm /m, Z = 2} \\ \qquad{\rm NaDS \quad a = 3,911(1) }\mathop {\rm A}\limits^\circ {\rm,\, b = 4,447(1) }\mathop {\rm A}\limits^\circ {\rm,\, c = 5,930(2) }\mathop {\rm A}\limits^\circ,\,\beta {\rm ={\hphantom{0}}99,55(2)}^\circ {\rm \,\,{bei}\,\, 9\, K} \\ \qquad{\rm KDS{\hphantom{a}}\quad a = 4,309(2) }\mathop {\rm A}\limits^\circ {\rm,\, b = 4,908(2) }\mathop {\rm A}\limits^\circ {\rm,\, c = 6,544(3) }\mathop {\rm A}\limits^\circ,\,\beta {\rm = 100,83(3)}^\circ {\rm \,\,{bei}\,\, 10\, K} \\ \qquad{\rm RbDS \quad a = 4,515(2) }\mathop {\rm A}\limits^\circ {\rm,\, b = 5,116(2) }\mathop {\rm A}\limits^\circ {\rm,\, c = 6,815(3) }\mathop {\rm A}\limits^\circ,\,\beta {\rm = 101,67(2)}^\circ {\rm \,\,{bei}\,\, 10\, K} \\ \end{array} $$\end{document} Umwandlungstemperaturen und -enthalpien der H- und D-Verbindungen werden mitgeteilt und die vorwiegend aus Neutronenbeugungsdaten von Deuterosulfiden ermittelten Atomanordnungen u.a. in Abhängigkeit von der Größe der Kationen diskutiert.
    Additional Material: 4 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
  • 10
    ISSN: 0044-2313
    Keywords: Aluminium sodium amide ; i. r., Raman spectra ; hydrogen bonding ; Chemistry ; Inorganic Chemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Description / Table of Contents: Lattice Vibration Spectra. LXXI Hydrogen Bonding and Synergetic Effect in Solid Amides: a Case Study for NaAl(NH2)4IR and Raman spectra (4000 - 200 cm-1, 90 K and 300 K) of NaAl(NH2)4 and of deuterated samples are recorded and discussed with respect to the bonding of NH2- ions in condensed phases compared to that of H2O molecules and OH--ions.The bands observed are assigned to the internal vibrations and librations of the NH2- ions and skeleton vibrations of the distorted tetrahedral Al(NH2)4- units (breathing vibration v1, 572 cm-1).Owing to the high charge density of the Al3+ ions the NH-stretching modes are shifted to higher wavenumbers by as many as 200 cm-1 compared to those of free amide ions. Furthermore the H-bond donor strenght of the NH2- ions is so much enlarged (synergetic effect) that weak, unusally long (d( … N) 〉 360 pm) NH2 … NH2 hydrogen bonds are formed. These H-bonds share layers of vertex connected Al(NH2)4 and Na(NH2)4 tetrahedra within the structure.
    Notes: IR- und Ramanspektren von NaAl(NH2)4 sowie von deuterierten Präparaten (4000-200 cm-1, 90 K und 300 K) werden mitgeteilt und im Hinblick auf das Bindungsverhalten von NH2--Ionen in kondensierter Phase im Vergleich zu der von H2O-Molekülen und OH--Ionen diskutiert.Die beobachteten Schwingungsbanden konnten den inneren Schwingungen und Librationen der NH2--Ionen sowie den Gerüstschwingungen verzerrt tetraedrischer Al(NH2)4--Ionen (AlN4-Pulsationsschwingung 572 cm-1) zugeordnet werden.Durch die hohe Ladungsdichte der Al3+-Ionen sind die NH-Streckschwingungen gegenüber denjenigen freier Amidionen um bis zu 200 cm-1 zu höheren Wellenzahlen verschoben. Ferner ist das H-Brückendonorvermögen der NH2--Ionen so stark erhöht, daß schwache, ungewöhnlich lange NH2 … NH2-Wasserstoffbrücken (d(N … N) 〉 360 pm) vorliegen. Diese verknüpfen Schichten eckenverknüpfter Al(NH2)4- und Na(NH2)4-Tetraeder.
    Additional Material: 5 Ill.
    Type of Medium: Electronic Resource
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...