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1998[X]
141Author    Hüseyin Kalkan, Sehriman Atalay, Ismet SenelRequires cookie*
 Title    EPR Study of the Dynamic Jahn-Teller Effect of Cu 2+ in CdBa(HC00) 4 -2H 2 0 Single Crystals  
 Abstract    Electron Paramagnetic Resonance spectra of Cu 2+ doped into cadmium barium formate dihydrate single crystal were studied at 300 K. The powder spectrum of this material was studied at 300 to 133 K. The values of the g and A hyperfine tensors were found to be temperature dependent. The temperature dependence of the Cu 2+ EPR spectrum is discussed in terms of the dynamic Jahn-Teller effect. The angular variation of the spectra indicates the substitution of the host Cd 2+ with Cu 2+ . The spectra were fitted with a tetragonal spin-Hamiltonian, the parameters of which were determined at 300 K. The ground-state wave function of the copper complex has been constructed at 113 K and 300 K. 
  Reference    Z. Naturforsch. 53a, 945—950 (1998); received October 6 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0945.pdf 
 Identifier    ZNA-1998-53a-0945 
 Volume    53 
142Author    F. Köksal, F. UcunRequires cookie*
 Title    EPR of 0 2 " Radicals in the Zeolites NH 4 NaY and NH 4 CaA  
 Abstract    Activated and non-activated states of the zeolites NH 4 NaY and NH 4 CaA, and their NH 4 forms were prepared with an (NH 4) 2 S0 4 solution and were investigated by EPR after 7-irradiation. The formed radicals were attributed to O-T supposed to be trapped near a trigonally coordinated framework of 27 A1 (I = 5/2). Anisotropic O^" spectra were observed, consisting of hyperfine structure due to the 27 Al framework, even at room temperature. This was attributed to the scarceness of NH 4 sites or trap sites because of the preparation of the NH 4 forms of the zeolites with an (NH 4) 2 S0 4 solution. The crystal field splittings were found and interpreted. 
  Reference    Z. Naturforsch. 53a, 951—954 (1998); received October 28 1998 
  Published    1998 
  Keywords    EPR, Zeolites, 0~, NH 4 NaY, NH 4 CaA 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0951.pdf 
 Identifier    ZNA-1998-53a-0951 
 Volume    53 
143Author    M. Jánossy, P. MezeiRequires cookie*
 Title    Excitation of the 210 nm Zn II Line in a Hollow Cathode He-Ne-Zn Discharge  
 Abstract    In a hollow cathode He-Zn discharge it was observed that addition of Ne stops laser oscillation at the 492.4 nm Zn II line and increases significantly the spontaneous intensity at the 210 nm Zn II line, which originates from the 4d 2 D 5/2 lower level of the laser transition. Based on a rate equation model, the cross-section of the Ne ion-Zn atom charge transfer collisions populating the 4d 2 D 5/2 level was determined. The cross-section 3.5x 10 -15 cm 2 found by us is in acceptable agreement with the value 2.3x 10" 15 cm 2 reported in the literature. This high cross-section together with existing lower level depopulation points to the possibility of obtaining laser oscillation at 210 nm in a Ne-Zn discharge. 
  Reference    Z. Naturforsch. 53a, 955—959 (1998); received April 6 1998 
  Published    1998 
  Keywords    Gas Lasers, Laser Excitation, Charge Transfer, Glow Discharges, Sputtering 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0955.pdf 
 Identifier    ZNA-1998-53a-0955 
 Volume    53 
144Author    Z. Akdeniz, M. P. TosiRequires cookie*
 Title    Ionic Conduction and Molecular Structure of Molten FeCl 3  
 Abstract    Former experiments on molten FeCl 3 have shown that, as for A1C1 3 , melting is accompanied by a transition from sixfold to essentially fourfold coordination. However, in contrast to AICI3, the FeCl 3 melt near freezing has an appreciable ionic conductivity. We propose a model for the structure of FeCl 3 melt as consisting of closely packed Fe 2 Cl 6 bitetrahedral molecules in equilibrium with (Fe 2 Cl 5) + and (Fe 2 Cl 7)" ionised species. 
  Reference    Z. Naturforsch. 53a, 960—962 (1998); received November 18 1998 
  Published    1998 
  Keywords    Melting, Liquid Structure, Molecular Liquids 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0960.pdf 
 Identifier    ZNA-1998-53a-0960 
 Volume    53 
145Author    A. Kapanowski, K. SokalskiRequires cookie*
 Title    Elastic Constants of Binary Liquid Crystalline Mixtures  
 Abstract    Microscopic expressions for the elastic constants of binary liquid crystalline mixtures composed of short rigid uniaxial molecules are derived in the thermodynamic limit at small distorsions and a small density. Uniaxial and biaxial nematic phases are considered. The expressions involve the one-particle distribution functions and the potential energy of two-body short-range interactions. The theory is used to calculate the phase diagram of a mixture of rigid prolate and oblate molecules. The concentration dependence of the order parameters and the elastic constants are obtained. The possibility of phase separation is not investigated. 
  Reference    Z. Naturforsch. 53a, 963—976 (1998); received September 24 1998 
  Published    1998 
  Keywords    Liquid Crystals, Nematics, Elastic Constants, Mixtures 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0963.pdf 
 Identifier    ZNA-1998-53a-0963 
 Volume    53 
146Author    OlegD. JefimenkoRequires cookie*
 Title    On the Experimental Proofs of Relativistic Length Contraction and Time Dilation  
 Abstract    Recent advances in the theory of electromagnetic retardation have made it possible to derive the basic equations of the special relativity theory and to duplicate the most important practical results of this theory without using the concepts of relativistic length contraction and time dilation. Thus the reality of these concepts appears to be questionable. It is imperative therefore to reexamine the experi-mental evidence supporting these concepts. The calculations presented in this paper show that some of the experiments allegedly proving the reality of length contraction and time dilation can be unambigu-ously interpreted as manifestations of velocity-dependent dynamical interactions taking place within the systems involved in the experiments rather than as manifestations of length contraction or time dilation. 
  Reference    Z. Naturforsch. 53a, 977—982 (1998); received August 21 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0977.pdf 
 Identifier    ZNA-1998-53a-0977 
 Volume    53 
147Author    Takahiro Ueda, Katsuyuki Shimizu, Hiroshi Ohki, Tsutomu OkudaRequires cookie*
 Title    C CP/MAS NMR Study of Motion and Local Structure of Phenethyl- ammonium Ion in [C 6 H 5 CH 2 CH 2 NH 3 ] 2 PbX 4 (X = Cl, Br, I)  
 Abstract    Ionic motion and local structure of phenethylammonium ion (C 6 H 5 CH-,CH 2 NH 3 +) in a series of phenethylammonium lead(II) halides, [C 6 H 5 CH 2 CH 2 NH 3 ] 2 PbX 4 (X = Cl, Br, I) were studied by means of 13 C cross polarization/magic angle sample spinning (CP/MAS) NMR technique. Among the three salts, remarkable differences in the spectra were observed in the signals corresponding to the phenyl carbons. The peaks from C2, C3, C5, and C6 in the phenyl group were split into three for the chloride and into two for the bromide, although in the iodide those were observed as a single peak. Coalescence of those peaks, as well as line broadening were observed on heating. This indicated that peak split brings about disorder of the orientation in the phenyl group around the C1-C4 axis, suggesting to have three and two orientations for the chloride and the bromide, respectively. Above room temperature the phenyl group undergoes chemical exchange among these orientations, and at higher temperature, reorientation with a large amplitude takes place around its axis. The apparent activation energies of the reorientation of the phenyl group for the chloride and bromide were estimated from the temperature dependence of the linewidth of the resonance peaks to be about 24 kJ mol -1 , 25 kJ mol -1 , respectively, which is similar to in the iodide (25.0 kJ mol -1). Ab initio molecular orbital energy calculation was carried out to evaluate the potential barrier of the internal rotation of the phenyl group in a free phenethylammonium ion. The intramolecular interaction was evaluated to be 13.9 kJ mol -1 from the calculation, and the intermolecular interaction results to be 10 kJmol -1 . 
  Reference    Z. Naturforsch. 53a, 983—988 (1998); received April 30 1998 
  Published    1998 
  Keywords    13 C CP/MAS NMR, Layered compound, Disorder, Reorientation, Activation energy 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0983.pdf 
 Identifier    ZNA-1998-53a-0983 
 Volume    53 
148Author    A. Galstian, M. StockhausenRequires cookie*
 Title    Dielectric Relaxation Study of Zn(N0 3 ) 2 , Cu(N0 3 ) 2 , Ni(N0 3 ) 2 , and Mg(N0 3 ) 2 Solutions in Water/DMSO Mixtures  
 Abstract    Dielectric spectra have been measured for the title systems up to 72 GHz at 20 °C with salt concen-trations <1 mol/1 and DMSO mole fractions of the mixed solvent in the 0.3 to 0.6 range. Results can be described by a superposition of two Debye terms (at lower frequencies) plus one Cole-Davidson term (at higher frequencies). The discussion is particularly focused on the lowest frequency term, which is related to ionic species. These are likely to consist in nonsymmetrically solvated cations rather than ion pair complexes. While Cu, Ni and Mg nitrates behave similarly, the Zn salt shows some differences which possibly are due to a change of the coordination number with increasing salt content. 
  Reference    Z. Naturforsch. 53a, 989—992 (1998) 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0989.pdf 
 Identifier    ZNA-1998-53a-0989 
 Volume    53 
149Author    J. Fleischhauer, A. Koslowski, Ch Repges, K.-R Gulden, G. BringmannRequires cookie*
 Title    The Absolute Configuration of Isoancistrocladine and 'Isohamatine' by Quantumchemical CD-Calculations  
 Abstract    The absolute configuration of the naphthylisoquinolines isoancistrocladine and isohamatine at the biaryl axis was determined by comparing the measured and the calculated CD spectra. In order to calculate these spectra we used the CNDO/S method in combination with a Boltzmann weighting of conformers with different dihedral angles at the biaryl axis. The Boltzmann factors were obtained with the AM 1 method. 
  Reference    Z. Naturforsch. 53a, 993—996 (1998); received November 3 1998 
  Published    1998 
  Keywords    Circular Dichroism, Biaryls, CNDO/S Method, AMI Method 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0993.pdf 
 Identifier    ZNA-1998-53a-0993 
 Volume    53 
150Author    V. Berbenni, A. Marini, D. CapsoniRequires cookie*
 Title    Solid State Reaction Study of the System Li 2 C03/Fe 2 03  
 Abstract    A thermoanalytical (TGA/DSC) and diffractometric (XRD) study has been performed on the solid state reaction system Li 2 C0 3 -Fe 2 0 3 in the x Li range 0.10-^0.50. A detailed analysis of the results shows that the data are in agreement with a reaction model where the carbonate decomposition is regulated by the formation of both LiFe0 2 and LiFe 5 0 8 , and the relative amount of the two phases depends on the initial composition. The DSC evidence offers the possibility to directly quantify the LiFe 5 O x phase. Fur-thermore it allows one to obtain the enthalpies of formation of both LiFe0 2 and LiFe 5 0 8 . 
  Reference    Z. Naturforsch. 53a, 997—1003 (1998) 
  Published    1998 
  Keywords    Lithium Ferrites, Solid State Reaction, Iron (III) Oxide, Lithium Carbonate, TGA, DSC 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0997.pdf 
 Identifier    ZNA-1998-53a-0997 
 Volume    53 
151Author    Singh Gill, Lindsay Byrne, TerryI. QuiekendenRequires cookie*
 Title    Cu Nuclear Magnetic Resonance and Viscosity Studies of Copper (I) Perchlorate in Mixed Solvents Containing Acetonitrile  
 Abstract    63 Cu nuclear magnetic resonance and viscosity studies of 0.064 M copper (I) Perchlorate solutions have been made at 298 K in binary mixtures of acetonitrile (AN) with dimethylsulphoxide (DMSO), hexamethylphosphotriamide (HMPA), N,N-dimethylacetamide (DMA), nitromethane (NM), propylene carbonate (PC) and 3-hydroxypropionitrile (3 HPN) at several compositions of the mixtures using a 500 MHz NMR Spectrometer and Ubbelohde viscometer, respectively. The chemical shift (S), linewidth (A) and line intensity (/) of the 63 Cu NMR signal in these mixed solvents have been measured relative to the 63 Cu signal in 0.064 M copper (I) Perchlorate (CuC104) solution in pure AN. The quadrupolar re-laxation rates (1/T2)q, reorientational correlation times (rR) and quadrupolar coupling constants (QCC) of the copper (I) solvates have also been estimated from the data. The QCC values show a big variation in all solvent systems with the change of solvent composition, indicating the formation of mixed com-plexes. The variation of all NMR parameters with solvent composition shows strong effects of DMSO, HMPA, and DMA on the solvation behaviour of Cu + in the first three mixtures, and relatively much weaker effects of PC, NM and 3HPN in the other three mixtures. 
  Reference    Z. Naturforsch. 53a, 1004—1008 (1998); received October 26 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-1004.pdf 
 Identifier    ZNA-1998-53a-1004 
 Volume    53 
152Author    Christian Ziegaus, ElmarW. LangRequires cookie*
 Title    Statistical Invariances in Artificial, Natural, and Urban Images  
 Abstract    To answer the question about the way our visual system processes images it has to work with every day, it is necessary to investigate the statistical structure of these pictures. For this purpose we investigated several ensembles of artificial and real-world greyscale images to find different invariance properties: translation invariance by determining an average pair-correlation function, scale invariance by investigating the power spectrum and the coarse graining of the images, and a new hierarchical invariance recently proposed [D. L. Ruderman, Network 5, 517 (1994)]. The results of our work indicated that the assumption of translational invariance can be taken for granted. Our results concerning the scale invariance are qualitatively the same as those found by Ruderman and others. The deviations of the distributions of the logarithmically transformed images from a Gaussian distribution cannot be seen as clearly as stated by Ruderman. This results from the fact that for a correct determination of the deviations the non-linear transformation must be considered. Depending on the preprocessing of the images the results concerning the hierarchical invariance differed widely. It seems that this new invariance can be confirmed only for logarithmically transformed images. 
  Reference    Z. Naturforsch. 53a, 1009—1021 (1998); received Oktober 31 1998 
  Published    1998 
  Keywords    Natural Images, Urban Images, Image Statistics, Invariance Properties of Images, Image Preprocessing 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-1009.pdf 
 Identifier    ZNA-1998-53a-1009 
 Volume    53 
153Author    Andreas Magauer, Soumitro Banerjee,Requires cookie*
 Title    Transmission of Binary Information with a Chaos Coded Communication System using QDPSK-Modulation  
 Abstract    Synchronisation of chaotic oscillators offers a way of practical application of the theory of Chaos in obtaining secure communication. In this work we introduce a nonautonomous chaotic system with sinusoidal external force for communication of binary signals. The information is applied to the phase position of the sinusoidal forcing signal of the chaotic oscillator using a quadrature difference phase shift keying (QDPSK) modulation. An inverse synchronisation system approach with direct modulation is applied. We describe the system in detail and discuss the requirements of a secure communication system. Issues related to bit error rate, transfer rate, signal to noise ratio, channel bandwidth, bandwidth efficiency and channel capacity are discussed, and the properties of the realized communication system are placed in relation to the requirements of a secure communication system. 
  Reference    Z. Naturforsch. 53a, 1022—1028 (1998); received November 20 1998 
  Published    1998 
  Keywords    Chaos, Synchronisation, Encryption, Communication, PSK-Modulation 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-1022.pdf 
 Identifier    ZNA-1998-53a-1022 
 Volume    53 
154Author    Th Holzhüter, Th KlinkerRequires cookie*
 Title    Control of a Chaotic Relay System Using the OGY Method  
 Abstract    The control method of Ott, Grebogi, and Yorke (OGY) is used to stabilize the unstable periodic orbits of a chaotic relay system. Small variations in the height of the relay output are used as control input. The influence of the control activation bound is studied in detail via the one-dimensional Poincare map of the controlled system. The reduced sensitivity of the multi-step OGY method for higher period orbits can thus directly be verified. 
  Reference    Z. Naturforsch. 53a, 1029—1036 (1998); received September 16 1998 
  Published    1998 
  Keywords    Control of Chaos, OGY Control Method, Relay System, Stabilization of Unstable Periodic Orbits, Poincare Map 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-1029.pdf 
 Identifier    ZNA-1998-53a-1029 
 Volume    53 
155Author    AshokK. Adya, Ryuzo Takagi, Marcelle Gaune-EscardRequires cookie*
 Title    Unravelling the Internal Complexities of Molten Salts  
 Abstract    Much experimental and theoretical effort has gone into revealing the internal complexities of molten salts for the past two decades. In this paper we shall show how neutron diffraction and computer sim-ulation techniques have helped in gaining a better understanding of these systems at the microscopic level. Firstly, a short review on the structure of molten halide systems as revealed by these techniques will be presented. Complementarity of using X-rays with neutrons and, some recent results on the struc-ture of molten DyCl 3 obtained by combining neutron and X-ray diffraction with molecular dynamic simulations will be discussed. Neutron diffraction isotopic substitution techniques have played an im-portant role in elucidating the interatomic structure of a diversity of molten salts. Pair distribution func-tions (PDFs), determined for a number of 1:1 and 2 :1 halide melts, provided theorists with a critical test of their model potentials. It is now clear that for 1:1 molten systems theoretical models based on Fumi-Tosi potentials can adequately describe many of the structural features. Nevertheless, the chal-lenge is two fold: (i) to determine real interatomic potentials for 2:1 and 3 :1 molten systems capable of reproducing not only the microscopic structural details obtained at the partial PDF, g a ß (r) level, but also their macroscopic behaviour and, (ii) to characterise the structure in binary molten salt mixtures. 
  Reference    Z. Naturforsch. 53a, 1037—1048 (1998); received November 18 1998 
  Published    1998 
  Keywords    Molten Salts, Structure, Neutron and X-ray Diffraction, Computer Simulations, Liquid State Structural Theory, Molten Halides 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-1037.pdf 
 Identifier    ZNA-1998-53a-1037 
 Volume    53 
156Author    Andre Wiesch3, Hauke Timmb, Karsten Bluhm3Requires cookie*
 Title    Uber CuDy2[B80 16] und CuHo2[B80 16]: Zwei neue "Metaborate" mit einem ^ [B80 16]g_-Anion On CuDy2[B80 16] and CuHo2[B80 16]: Two New "Metaborates" with a ^ [B80 16]8-Anion  
 Abstract    Nearly colourless single crystals of the compounds CuDy2 [B80 i 6] (I) and CuHo2[B80)6] (II) have been obtained by a B20 3 flux technique. They crystallize in the structure of CuTb2 [B80)6] (I) or in an orthorhombic variant (II). X-ray investigations on single crystals led to the space group C2h -P2!/c (Nr. 14) with lattice parameters a = 1025,5(10); b = 836,99(10); c = 621,2(8) pm, ß = 90.47(10)°; Z = 2 (I) and D^h -Pbam (Nr. 55) with a = 840,7(2), b = 616,6(2), c = 1022,0(2) pm, Z = 2 (II). The structures contain 1 [B80 16]8_ chains isolated from each other, which include tri-and tetracoordinated boron, T'fie chains consist of alternating twelve and eight-membered rings of boron and oxygen atoms connected by B 0 4 units. Dy,+ and H o 3+ are octacoordinated and Cu2+ is hexacoordinated in elongated octahedra by oxygen. The relation between these two structures is discussed. 
  Reference    (Z. Naturforsch. 53b, 1—4 [1998]; eingegangen am 23. Oktober 1997) 
  Published    1998 
  Keywords    Copper, Lanthanoids, Borate, Synthesis, Crystal Structure 
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 TEI-XML for    default:Reihe_B/53/ZNB-1998-53b-0001.pdf 
 Identifier    ZNB-1998-53b-0001 
 Volume    53 
157Author    Lanthanoid Borates, A. Wiesch, K. BluhmRequires cookie*
 Title    CuHo2[B20 5]2* Ein unerwarteter Strukturtyp in der Reihe der Kupferlanthanoidborate CuHo2[B20 5]2: An Unexpected Structure Type in the Series of Copper  
 Abstract    Single crystals of the new compound CuHo2 [B20 5 ]2 were obtained by using a B20 3 flux technique with CuO and Ho20 3 at 1050 °C. X-ray investigations on single crystals led to the space group P 2,/c (Nr. 14) with lattice parameters a = 454.3(2); b = 726.0(4); c = 936.0(5) pm; ß = 90.77(1)°; Z = 2. The compound is isotypic to CuTb2[B20 5 ] 2 as well as to the gadolinite structure (FeY2 [BeSi05]2). The structure exhibits layer-like 2 [B20 5]4~, a two-dimensional anion consisting of edge sharing B 0 4 -tetrahedra, which form four-and eight-membered rings. The layers are connected by elongated C u06-octahedra and slightly distorted tetragonal LnOs-antiprisms. 
  Reference    (Z. Naturforsch. 53b, 5—8 [1998]; eingegangen am 23. Oktober 1997) 
  Published    1998 
  Keywords    Copper, Holmium, Borate, Synthesis, Crystal Structure 
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 TEI-XML for    default:Reihe_B/53/ZNB-1998-53b-0005.pdf 
 Identifier    ZNB-1998-53b-0005 
 Volume    53 
158Author    SvetlanaN. Nikolaeva3, EvgeniV. Avtomonov, Jörg Lorberthb, ValeryS. Petrosyan3Requires cookie*
 Title    The Reaction of Bis[bis(trimethylsilyl)amino]germylene with Bromocyanogen and the Crystal Structure of Bis[bis(trimethylsilyl)amino]bromocyanogermane  
 Abstract    Bis[bis(trimethylsilyl)amino)]germylene (1) reacts with bromocyanogen to give bis[bis(trimethylsilyl)amino]bromocyanogermane (2). 2 crystallises from petroleum ether as a colourless solid which has been characterised by IR, H,I3C, 29Si NMR spectroscopy, ele­ mental analysis and X-ray diffractometry. 
  Reference    (Z. Naturforsch. 53b, 9—12 [1998]; received October 7 1997) 
  Published    1998 
  Keywords    Germanium, Germylene, Germyl Cyanide, X-Ray Data 
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 TEI-XML for    default:Reihe_B/53/ZNB-1998-53b-0009.pdf 
 Identifier    ZNB-1998-53b-0009 
 Volume    53 
159Author    J. Seemann, W. PreetzRequires cookie*
 Title    Schwingungsspektren und Normalkoordinatenanalyse von Hexathiocyanatoplatinat(IV), Kristallstruktur von [Py2CH2][Pt(SCN)6] Vibrational Spectra and Normal Coordinate Analysis of Hexathiocyanatoplatinate(IV), Crystal Structure of [Py2CH2][Pt(SCN)6]  
 Abstract    By treatment of [PtCl6]2-with an excess of SCN~ in aqueous solution [Pt(SCN)6]2~ is formed. The X-ray structure determination on a single crystal of [Py2CH2][Pt(SCN)6] (orthor-hombic, space group Pna21? a = 15.5084(9), b = 11.8444(11), c = 13.2830(9)A, Z = 4) shows, that the thiocyanate groups are exclusively S-coordinated with average Pt-S distances of 2.378 A and Pt-S-C angles in the range from 103.1° to 108.1°. Based on the molecular parameters of the X-ray determination the low temperature (10 K) IR and Raman spectra have been assigned by normal coordinate analysis. The valence force constant is fd(PtS) = 1.62 mdyn/A. 
  Reference    (Z. Naturforsch. 53b, 13—16 [1998]; eingegangen am 15. Oktober 1997) 
  Published    1998 
  Keywords    Hexathiocyanatoplatinate(IV), IR Spectra, Raman Spectra, Normal Coordinate Analysis, Crystal Structure 
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 TEI-XML for    default:Reihe_B/53/ZNB-1998-53b-0013.pdf 
 Identifier    ZNB-1998-53b-0013 
 Volume    53 
160Author    Sabine Schlecht, Soheila Chitsaz, Bernhard Neumüller, Kurt DehnickeRequires cookie*
 Title    Die Kristallstrukturen des Diphenylphosphinsäureamids, Ph2P(0)NH 2, und seines Cäsiumsalzes [Cs{Ph2P(0)NH}] Crystal Structures of Diphenylphosphinic Acid Amide, Ph-,P(0)NH-, and of its Cesium Salt [Cs{Ph2P(0)NH}]  
 Abstract    The crystal structures of the monoclinic form of Ph2P(0)NH2 and of its cesium salt, [Cs{Ph2P(0)NH}l have been determined by X-ray methods. Ph2P(0)N H 2: Space group P2,/c, Z = 16, lattice dimensions (-80°C): a = 2530.2(3), b = 858.9(2), c = 2135.5(3) pm, ß = 110.78(1)°, R , = 0.055. Diphenylphosphinic acid amide forms dimeric molecules via N-H- • O hydrogen bonds, the dimeric units again are associated via hydrogen bonds to form infinite double chains along the crystallographic c axis. [Cs{Ph2P(0)NH}]: Space group Pccn, Z = 8 , lattice dimensions (-83°C): a = 1262.8(1), b = 2632.3(2), c = 769.1(1) pm , R\ = 0.024. The compound is associated via Cs-O and Cs-N contacts along the crystallographic [001] axis forming a tubular arrangement. There are no hydrogen bonds. 
  Reference    (Z. Naturforsch. 53b, 17—22 [1998]; eingegangen am 3. November 1997) 
  Published    1998 
  Keywords    Phosphinic Acid Amide, Cesium, Crystal Structure 
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 TEI-XML for    default:Reihe_B/53/ZNB-1998-53b-0017.pdf 
 Identifier    ZNB-1998-53b-0017 
 Volume    53 
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