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1981 (332)
81Author    G. Abou-Elenien+, J. Rieser++, N. Ismail+++, K. WallenfelsRequires cookie*
 Title    Elektrochemische Eigenschaften von Dihydropyridin-und Pyridinderivaten Electrochemical Properties of Pyridine and Dihydropyridine Derivatives  
 Abstract    The electrochemical oxidation and reduction properties of different dihydropyridines and pyridines have been investigated in non aqueous solvent as benzonitrile and aceto-nitrile with tetra-n-butylammonium perchlorate as supporting electrolyte at platinium electrodes using DC-voltametry, cycl. voltametry and coulometry. Possible redox-mechanisms are discussed. 
  Reference    Z. Naturforsch. 36b, 386—390 (1981); eingegangen am 26. November 1980 
  Published    1981 
  Keywords    Pyridines, Dihydropyridines, Electrochemical Behavior, Redox-Potentials 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0386.pdf 
 Identifier    ZNB-1981-36b-0386 
 Volume    36 
82Author    G. Abou-Elenien+, J. Rieser++, N. Ismail+++, K. WallenfelsRequires cookie*
 Title    Kinetische Untersuchungen zur Wasserstoffübertragung von Dihydropyridinen auf Hydrazyle Kinetic Investigation on the Hydrogen Transfer from Dihydropyridines to Hydrazyls  
 Abstract    The results of a kinetic study on the hydrogen transfer between different dihydro-pyridines and mono-, bis-and trishydrazyls of the tricyanobenzene series are described. The reactions have been found to obey in all cases a second-order law. The influences of solvent medium, redox-potentials of the reactants and temperature on the rates of reactions have been investigated. 
  Reference    Z. Naturforsch. 36b, 391—394 (1981); eingegangen am 26. November 1980 
  Published    1981 
  Keywords    Dihydropyridines, Hydrazyls, Hydrogen Transfer, Kinetics 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0391.pdf 
 Identifier    ZNB-1981-36b-0391 
 Volume    36 
83Author    Rainer Lößberg, Ulrich MüllerRequires cookie*
 Title    A Method for the Preparation of Anhydrous Ruthenium (VIII) Oxide  
  Reference    Z. Naturforsch. 36b, 395 (1981); eingegangen am 3. Dezember 1980 
  Published    1981 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0395_n.pdf 
 Identifier    ZNB-1981-36b-0395_n 
 Volume    36 
84Author    Rosangela Battaglia, Rainer Henning, Horst KischRequires cookie*
 Title    Photoproduction of Hydrogen from Water Catalysed by Metal Sulfur Chelates  
 Abstract    Photoreduction of Water, Catalysis, Metal Sulfur Chelates Metal dithiolenes and other sulfur containing metal complexes catalyse the photoproduction of hydrogen from water in the presence of tetrahydro-or dihydrofurans. Catalysed photochemical generation of hydrogen from water in homogeneous solution is known to occur only in the presence of a reducing agent and a multicomponent catalyst system composed of a sensitizer, e.g. tris(2,2'-bipyridine)Ru 2+ , an electron relay species, e.g. N,N'-(fimethyl-4,4'-bipyridinium-chloride, and of a redox catalyst like colloidal platinum [1-6]. The two latter components may be omitted on the expense of catalytic activity [7]. We recently discovered simple and very efficient cata-lytic systems consisting of a metal dithiolene cata-lyst and a reducing agent only [8 a]. In the present communication we report on the ability of a large number of metal sulfur chelates to catalyse the photoproduction of hydrogen from water in homo-geneous solution [8 b]. 
  Reference    Z. Naturforsch. 36b, 396—397 (1981); received December 1 1980 
  Published    1981 
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 Identifier    ZNB-1981-36b-0396_n 
 Volume    36 
85Author    Rafet Aydin, Harald GüntherRequires cookie*
 Title    3 C, X H Spin-Spin Coupling Constants, VIII 2-Methyl-and 3,5-Dimethyladamantane  
 Abstract    One-bond, geminal and vicinal 13 C, X H coupling constants have been determined for 2-methyl-and 3,5-dimethyladamantane using the deriva-tives deuterated in position 2 and 1, respectively, and the relation «JpC, 1 !!) = 6,5144 "J(13 C, 2 H) for the conversion of the measured "J(13 C, 2 H) values. The effect of methyl-substitution on these parameters is discussed. 
  Reference    Z. Naturforsch. 36b, 398—399 (1981); eingegangen am 17. November 1980 
  Published    1981 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0398_n.pdf 
 Identifier    ZNB-1981-36b-0398_n 
 Volume    36 
86Author    V. N. Babin, V. V. Gumenyuk, S. P. Solodovnikov, YuA. BelousovRequires cookie*
 Title    A Spin Trap Investigation of Azolyl Radicals  
 Abstract    Spin Trap Investigation, Azolyl Radicals An ability of azolyl-anions to behave as one-electrons reductans in reactions with f-nitro-sobutane and iron carbonyls are found in solu-tions. The azolyl radicals formed in reaction of azolyl-anions and azoles with £-BuNO have been trapped as corresponding nitroxide radicals. The formation of radicals from azoles can be described as consequence of proton and electron transfer acts. Radicals derived from regular azoles have so far been detected only in low-temperature matrices [1-3]. No data on the existence of azolyl radicals in solutions has been reported. To generate and detect these radicals we have taken advantage of the fact that tertiary nitrosobutane (1) rountinely used as a spin trap may also act as a one-electron reducing agent with respect to certain anionic nucleophyls [4]. We have found that in THF solutions such azole anions as imidazole, pyrazole, benzotriazole and adenine (in the form of sodium salts) react with 1 to form azolyl radicals which later exhibit conversation into stable azolyl4erf-butylnitroxyls (2). The ESR spectra of the final products consist of a triplet of equal intensity triplets due to splitting on the nitrogens to the nitrozyl fragment and heterocycle. Az-+ £-BuNO -> Az-+ f-BuNO T (1) Az-+ *-BuNO Az-N4-Bu (2) i 
  Reference    Z. Naturforsch. 36b, 400—401 (1981); received November 4 1980 
  Published    1981 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0400_n.pdf 
 Identifier    ZNB-1981-36b-0400_n 
 Volume    36 
87Author    Otto Vostrowsky, Karl MichaelisRequires cookie*
 Title    Methoxymerkurierung-Demerkurierung von Pheromonen zur Bestimmung der Doppelbindungsposition Methoxymercuration-Demer curation of Pheromones for Double Bond Position Determination  
 Abstract    Methoxymercuration-demercuration, Pheromones Methoxymercuration-demercuration of al-kenyl acetates and alkenols yields methoxy-derivatives which were analysed by mass spectro-metry to determine the original double bond position. Zur Bestimmung der Position der Doppelbindun-gen olefinischer Lepidopterenpheromone und deren Strukturanaloga mittels GC-kombinierter Massen-spektroskopie untersuchten wir die Methoxy-merkurierungsreaktion und ihre Verwendbarkeit als analytische Methode. Diese Reaktion, die bei unge-sättigten Estern bereits zur massenspektrometri-schen Doppelbindungsbestimmung herangezogen wurde [1], ist von uns an Alkenylacetaten und Alke-nolen, wie sie als Sehmetterlings-Sexuallockstoffe vorkommen [2], getestet worden. Eine jüngst er-schienene Arbeit über die Ermittlung von Doppel-bindungspositionen in cuticularen Lipiden von Insekten [3] zwingt uns zu einer vorläufigen Ver-öffentlichung unserer Ergebnisse. Die Behandlung von Olefinen 1 mit Hg(OAc)2 und CH3OH führt zu zwei positionsisomeren Methoxy-mercuri-derivaten, die mit NaBH 4 zu den Methoxy-alkanen 2a und b demerkuriert werden (Schema 1). Schema 1. R'-OUHC-R 2 1 1) Hg(OAc)2/CHjOH 2) NaBHt 
  Reference    Z. Naturforsch. 36b, 402—404 (1981); eingegangen am 24. Oktober 1980 
  Published    1981 
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 Identifier    ZNB-1981-36b-0402_n 
 Volume    36 
88Author    Walter AbrielRequires cookie*
 Title    Die Kristallstruktur von Te6OnCl2 The Crystal Structure of Te60iiCl2  
 Abstract    Crystals of the title compound are monoclinic (space group P2i/m) with a — 6.844(4) Ä, 6 = 6.800(4) Ä, c= 15.227(9) A, y= 120.19° and Z = 2. The structure contains infinite cationic [(Tei2C>22) 4+ ]oo -chains with three different sites for tellurium. There are three oxygen atoms in a y-tetrahedral arrangement around Tel, and four oxygen atoms in a y-trigonal-bipyramidal coordination around Te2 and Te3. 
  Reference    Z. Naturforsch. 36b, 405—409 (1981); eingegangen am 28. Januar 1981 
  Published    1981 
  Keywords    System Te02-TeCl4, Ternary Compounds, Crystal Structure, Lone-Pair Electrons 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0405.pdf 
 Identifier    ZNB-1981-36b-0405 
 Volume    36 
89Author    Wolfgang Dörrscheidt, Herbert SchäferRequires cookie*
 Title    Zur Kenntnis des Bariumthioantimonats(III) Ba8Sb6S17 On Bariumthioantimonate(III) BasSböSi?  
 Abstract    Bariumthioantimonate(III), Crystal Structure BagSbeSiy, prepared by fusion of the binary sulfides at 1120 K, crystallizes in the mono-clinic system (space group: P 2/c) with a= 1141 ± lpm, 6 = 1373 ± lpm, c = 2253 ± 2 pm, ß = 90.94 ± 0.05°. In the structure there are isolated distorted SbS3 3_ -trigonal pyramids (y-tetrahedra) and hitherto unknown Sb3Ss 7--units consisting of a central SbS4-y-trigonal bipyramid con-nected by the common axial S-atoms with two further SbS3 3 ~ groups. 
  Reference    Z. Naturforsch. 36b, 410—414 (1981); eingegangen am 30. Januar 1981 
  Published    1981 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0410.pdf 
 Identifier    ZNB-1981-36b-0410 
 Volume    36 
90Author    Brigitte Eisenmann, Herbert SchäferRequires cookie*
 Title    Zintlphasen mit binären Anionen: Zur Kenntnis von BaGe2P2 und BaGe2As2 Zintl Phases with Binary Anions: BaGe2P2 and BaGe2As2  
 Abstract    The new isotypic compounds BaGe2P2 and BaGe2As2 crystallize in the tetragonal system (P42mc) with the following lattice constants: 
  Reference    Z. Naturforsch. 36b, 415—419 (1981); eingegangen am 22. Dezember 1980 
  Published    1981 
  Keywords    Intermetallic Valence Compounds, Zintl Phases, Crystal Structure 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0415.pdf 
 Identifier    ZNB-1981-36b-0415 
 Volume    36 
91Author    Henk Van Dam, Andries Terpstra, Ad Oskam, JanH. TeubenRequires cookie*
 Title    UV Photoelectron Spectra of Some Bent Bis(r; 5 -cyclopentadienyl)Niobium and Tantalum Complexes  
 Abstract    He(I) and He(II) photoelectron spectra are reported for (/^-CsHs^MLX (M = Nb, Ta; L = H, CO; X — propene, 1-butene, propyl) and some methylcyclopentadienyl deriva-tives. Also the spectra of some yr-allyl and dihalide complexes are reported. Unambiguous assignments could be made of the metal d ai orbital, the Cp orbitals, the olefin n ionization and the M-hydride and 7t-allyl orbitals. Very regular trends are observed in the ionization energies upon substitution of the ligands. The olefin n ionization is found at very low energy indicating that the n backbonding to the olefin is very important. He(I)/He(II) cross section differences show clearly differences in metal character of the various M.O.'s. 
  Reference    Z. Naturforsch. 36b, 420—425 (1981); received December 29 1980 
  Published    1981 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0420.pdf 
 Identifier    ZNB-1981-36b-0420 
 Volume    36 
92Author    Alexius Darmadi, Alois Haas, Klaus TebbeRequires cookie*
 Title    Beiträge zur Chemie der Trifluormethylseleninsäure, Redoxprozesse im F3CSe-0-SCF7iCl3n-Sy8tem 0 Contributions to the Chemistry of Trifluoromethylseleninic Acid, Redox Processes in the F3CSe(0)0SCF"Cl3_" System  
 Abstract    Reactions of F3CSe(0)0Ag with F"Cl3_nCSCl (n = 3, 2, 1) give the compounds F3CSeS(02)CFnCl3-n. These decompose in the range of— 20 °C to 39 °C to F3CSeCF"Cl3_" plus S02. IR, NMR and mass spectra of the newly prepared compounds are presented. 
  Reference    Z. Naturforsch. 36b, 426—430 (1981); eingegangen am 12. Januar/11. Februar 1981 
  Published    1981 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0426.pdf 
 Identifier    ZNB-1981-36b-0426 
 Volume    36 
93Author    Moisés MoránRequires cookie*
 Title    Reactions of (»?-C5H5)Co(CO)2 and (??-EtMe4C5)Co(CO)2 with Iodine and Cyanogen Halides, XCN (X = Br OR I)  
 Abstract    Cyanogen Halides The title compounds react with iodine to give the iodinecarbonyl complexes (*7-C5H5)Co(CO)l2 and (j?-EtMe4C5)Co(CO)l2. The reactions of the same compounds with the cyanogen halides XCN (X = Br or I) give rise to the formation of mixed cyano-carbonyl complexes (^-C5H5)Co(CO)(CN)X and (7?-EtMe4C5)Co(CO)(CN)X (X = Br or I) respectively. The compounds have been characterized by elemental analyses and IR and HNMR spectra. 
  Reference    Z. Naturforsch. 36b, 431—433 (1981); received January 19 1981 
  Published    1981 
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 Identifier    ZNB-1981-36b-0431 
 Volume    36 
94Author    M. Morán, M. GayosoRequires cookie*
 Title    Reactions of Biscyclopentadienyl Vanadium with NO and XNO (X = Cl OR Br)  
 Abstract    Biscyclopentadienyl Vanadium The reactions of (^-CSHS^V with NO and XNO (X = CL or Br) lead to the formation of [?7-C5H5V(N0)2]2 and (j?-C5H5)2VX(NO) (X = CL or Br) respectively. The compounds have been characterized by elemental analysis, magnetic moments and IR and EPR spectra. 
  Reference    Z. Naturforsch. 36b, 434—436 (1981); received January 29 1981 
  Published    1981 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0434.pdf 
 Identifier    ZNB-1981-36b-0434 
 Volume    36 
95Author    Martin DrägerRequires cookie*
 Title    5-Chlor-5-phenyl-l-oxa-4.6-dithia-5-stannocan, ein diplanarer Übergangszustand bei der Racemisierung der Wanne-Sessel- Konformation in einem 8-Ring [1] 5-Chloro-5-phenyl-l-oxa-4,6-dithia-5-stannocane, a Diplanar Transition State for the Racemisation of the Boat-Chair Conformation in an Eight-Membered Ring [1]  
 Abstract    The title compound has been synthesized from PhSnCl3 and the disodium salt of bis(2-mercaptoethyl)ether. The crystal structure has been determined and refined to R — 0.033. The conformation of the eight-membered heterocycle is slightly disordered and represents a diplanar form, which is generally considered the transition state near the saddle point of the energy surface between the two enantiomers of the boat-chair con-formation. The configuration around tin is a trigonal bipyramid with equatorial sulfur atoms, an equatorial phenyl group and with axial atoms CI and O (transannular distance Sn--0 241 pm). 
  Reference    Z. Naturforsch. 36b, 437—440 (1981); eingegangen am 4. Februar 1980 
  Published    1981 
  Keywords    Tin, Heterocycles, Conformation, Transition State 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0437.pdf 
 Identifier    ZNB-1981-36b-0437 
 Volume    36 
96Author    Frank Kübel, Joachim SträhleRequires cookie*
 Title    Polymere Dimethyl-und Diphenylglyoximatokomplexe des Cobalts und Eisens mit Pyrazin als Brückenligand. Die Kristallstruktur des Bis(dimethylglyoximato)pyrazin-cobalt(II) + Polymeric Dimethyl-and Diphenylglyoximato Complexes of Cobalt and Iron with Pyrazine as a Bridging Ligand. The Crystal Structure of Bis(dimethylglyoximato)pyrazine Cobalt(II)+  
 Abstract    Polymeric bis(dimethyl-and diphenylglyoximato)-complexes of Fe(II) and Co(II) with pyrazine as a bridging ligand have been synthesized. The Co(II) complexes are para-magnetic with n = 1.83 B.M., and surprisingly stable against oxidation. Bis (dimethyl-glyoximato)pyrazine-cobalt (II) crystallizes monoclinic in the space group C2/m with Z = 2. The crystal structure shows linear chains of alternating Co atoms and pyrazine ligands. Perpendicular to the chain, the Co atoms are coordinated in a square planar arrangement by two dimethylglyoximato ligands (Co-N= 189 pm), the local symmetry being C2h-The long Co-pyrazine distance of 224 pm is in agreement with the fact that the compound is a 19 electron complex. The Co complexes do not have conducting properties. The Fe(II) complexes possess the same structure but with stronger bonds in the chain. They show very low conductivity of approximately 10 -10 cm -1 Q~ l . The Mössbauer spectra of the Fe-complexes are reported. 
  Reference    Z. Naturforsch. 36b, 441—446 (1981); eingegangen am 16. Januar 1981 
  Published    1981 
  Keywords    Iron and Cobalt Glyoximato Pyrazine Complexes, Synthesis, Crystal Structure 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0441.pdf 
 Identifier    ZNB-1981-36b-0441 
 Volume    36 
97Author    Rolf Appel, Und Volker, Ingo GläselRequires cookie*
 Title    Isolierbare  
 Abstract    Chlor [(thio)alkoxy] triorganylphosphoniumchloride als Zwischenprodukte der Oxiran (Thiiran)-Halogenierung mit Dichlorphosphoranen [1] Isolable Chloro[(thio)alkoxy]triorganylphosphoniumchlorides as Intermediates of the Oxirane (Thiirane)-Halogenation with Dichlorophosphoranes [1] Isolable chloro[(thio)alkoxy]triorganylphosphoniumchlorides RR2'P-X-CH2R"] + C1 _ are synthesized by reaction of oxiranes (2-5) (oxetane (6), thiiranes (18a-c)) with dichloro-phosphoranes (la-f). Structure and stability are discussed. Thermal Arbusov-rearrange-ment yields vicinal di-resp. trihalo-alkanes and phosphanoxides. The structures are confirmed by 3ip{iH} and isqiH} NMR data. 
  Reference    Z. Naturforsch. 36b, 447—450 (1981); eingegangen am 12. Dezember 1980 
  Published    1981 
  Keywords    Halogenation, Oxiranes, Thiiranes, Dichlorophosphoranes, Chloro[(thio)alkoxy]phosphonium Salts 
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 Identifier    ZNB-1981-36b-0447 
 Volume    36 
98Author    Ridvan Talay, Dieter RehderRequires cookie*
 Title    Carbonylvanadium  
 Abstract    , -mangan-und -molybdänkomplexe mit den Liganden o-C6H4EPh2(E Ph2) (E, E = P, As, Sb, Bi) und cis-Ph2PCH=CHPPh2 Carbonylvanadium, -manganese and -molybdenum Complexes of the Ligands o-C6H4EPh2(E'Ph2) (E, E' = P, As, Sb, Bi) and cis-Ph2PCH=CHPPh2 The photo-induced reaction between the complexes [Et4N][V(CO)6] (1), j? 5 -C5H5V(CO)4 (2), f? 5 -C5H5Mn(CO)3 (3) or 7? 5 -C5H5Mo(CO)3CH3 (4) and the ligands o-C6H4EPh2(E'Ph2) (E = E' = P: a; E = P, E'=As: b; E = E'= As: C; E = P, E'=Sb: d; E = P, E'= Bi: e; E = As, E' = Sb: f) and ds-Ph2PCH = CHPPh2 (g), L, yields -depending on the steric requirement of L -the compounds (M}L ({M} = cw-V(CO)4-, eis-CpV(CO)2, CpMn(CO), CpMo(CO)CH3; L = a, b, c, g), {M'}L ({M'j = V(CO)5-, L -d; {M'} -CpV(CO)3, L -d, e; {M'} = CpMn(CO)2, L = e) or mixtures of {M}L and (M'}L ({M}, {M'} = V(CO)4,5, L = e,f; {M}, {M'} = CpV(CO)2>3, L = f). In the mono-substituted species {M'}L coordination (as indicated by the 51 V NMR spectra) occurs through EPh2 and E'Ph2, which is explained by a reaction path via a labile chelate 5-ring structure. Shielding of the 51 V nucleus decreases in the order g > SbPh2 > PPh2 > AsPh2 > BiPh2 (derivatives of 1) and g > SbPh2 > PPh2 > BiPh2 >AsPh2 (derivatives of 2), and is smaller in the rigid chelates incorporating the o-phenylene ligands than in the more flexible structures of phospha-and arsabutane complexes. This fact is discussed in terms of hindered <7-overlap due to distortion of the EVE angle, which also results in an increase of CO valence force constants in rigid chelates. 31 P coordination shifts increase according to dppe < a < g and arphos < b (dppe = Ph2P(CH2)2PPh2, arphos = Ph2As(CH2)2PPh2). 31 P NMR spectra of the molybdenum complexes suggest that the basic geometry for 4 a and 4 b likely is tetragonal pyramidal, while the preferred structure for 4 g appears to be the trigonal bipyramid with the ligand in equatorial positions. The crystal and molecular structure of 1 a is reported. The complex crystallizes in the space group C2/c (a = 2196.0, b= 1080.1, c = 2022.7 pm, ß= 124.6°). The most striking result is the small PVP angle of 80.8 (0.2)°. Optimized methods for the synthesis of the ligands a-f are described; the ligands are characterized by their mass spectra. 
  Reference    Z. Naturforsch. 36b, 451—462 (1981); eingegangen am 4. Dezember 1980 
  Published    1981 
  Keywords    Carbonylphosphinevanadium, Vanadium-NMR, Phosphorus-NMR 
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 Identifier    ZNB-1981-36b-0451 
 Volume    36 
99Author    R. Schmelczer, D. Schwarzenbach, F. HulligerRequires cookie*
 Title    On the Rare-Earth Pnigochalcogenides LnAsSe  
 Abstract    Inorganic Compounds, Crystal Structure The structures of GdAsSe and NdAsSe were determined from single crystal data. GdAsSe crystallizes in the monoclinic CeAsS-type structure. The deviations from the parent tetragonal ZrSiS-type structure are smaller than in the corresponding sulphides. The As-As distances in the infinite arsenic chains appear to be too large to warrant non-metallic properties. The structure of NdAsSe is isopuntal with the CeAsS-type; however, only As pairs can be identified. The CeAsS-type structure was also found in the LnAsSe compounds with Ln = Pr, Sm, Tb, . . ., Tm, Lu, Y. The distortions of the ZrSiS-type substructure become more pronounced on going to smaller cations. The stoichiometry of the samples depends strongly upon the preparation. 
  Reference    Z. Naturforsch. 36b, 463—469 (1981); received October 31/December 17 1980 
  Published    1981 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0463.pdf 
 Identifier    ZNB-1981-36b-0463 
 Volume    36 
100Author    Jacek Bielawski, Kurt Niedenzu, Annelore Weber, Wilhelm WeberRequires cookie*
 Title    Cyclic Boron Derivatives of Biurets [1]  
 Abstract    Boron Compounds, l,3,5-Triaza-2-boracyclohexa-4,6-diones, Bis(N,N',N"-trimethylbiuret-l,5-diyl)borates(l-), NMR Spectra Several l,3,5-triaza-2-boracyclohexa-4,6-diones have been prepared by condensation reactions of boranes with biurets; N-methylated species could be characterized by their 1 H, U B and 13 C NMR spectra. Some data are also reported on bicyclic bis(N,N',N"-trimethylbiuret-l,5-diyl)borate(l-) salts and on a betaine consisting of two N,N',N"-tri-methylbiuret moieties bonded to a central four-coordinate boron atom. 
  Reference    Z. Naturforsch. 36b, 470—473 (1981); received January 19 1981 
  Published    1981 
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 TEI-XML for    default:Reihe_B/36/ZNB-1981-36b-0470.pdf 
 Identifier    ZNB-1981-36b-0470 
 Volume    36 
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