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1998[X]
81Author    A. Ishikawa, M. Kurasawa, S. Kitahara, A. Sasane, N. Kojima, R. IkedaRequires cookie*
 Title    A 35 C1 NQR Study on CS 2 [AU I C1 2 ] [Au m Cl 4 ]  
 Abstract    A pair of 35 C1 NQR spin echo signals has been observed for the mixed valence complex Cs 2 [Au'Cl 2 ] [Au'^C^] between 77 and 243 K. At 77 K, two resonance lines with the half widths Av Q ~ 50 kHz were located at v Q1 = 17.28 MHz for the Au'-Cl chlorine and at v Q2 = 27.10 MHz for the Au m -Cl chlorine in accordance with the crystal structure. The chlorine ionic characters of the Au'-Cl and Au'"-Cl bonds are estimated as 0.63 and 0.42, respectively. The central gold atom carries a fractional protonic charge of 0.26 in [AU'C1 2 ]~ and 0.68 in [Au"'Cl 4 p. The charge distributions in the complex anions differ in-significantly from those in the isolated [AUC1 2 ]~ and [AUC1 4 ]" for ordinary complexes, indicating that the charge transfer interactions between the anions are weak in the mixed valence complex. The ob-served linear temperature dependencies of Vg and log T lQ are well explained by the lattice vibration. When the temperature was increased from 77 K, the resonance lines became gradually weak without changing AV q and immeasurable above 215 K. ESR spectra taken at various temperatures revealed the presence of paramagnetic sites of ca. 5x 10 2<) mol -1 arising from Au(II). The small but finite concen-tration of Au(II) or some other reason should be responsible for the fade out phenomenon and the large Avq observed. 
  Reference    Z. Naturforsch. 53a, 590—594 (1998); received December 31 1997 
  Published    1998 
  Keywords    35 C1 NQR Frequency, 35 C1 NQR Spin-lattice Relaxation, Mixed Valence Gold Complex, Charge Transfer Interaction, ESR 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0590.pdf 
 Identifier    ZNA-1998-53a-0590 
 Volume    53 
82Author    J. K. Jung, Y. M. Seo, S. H. ChohRequires cookie*
 Title    Na NMR and 14 N NQR in Mixed Crystals Na,_ x Ag x N0 2  
 Abstract    The 23 Na (/= 3/2) NMR powder pattern for the m = 1/2 m = —1/2 transition, broadened by the second-order quadrupole interaction, was investigated in mixed crystals Na!_ x Ag x N0 2 (x<0.16). From the intensity loss of the 23 Na NMR line caused by the Ag + -impurity, the range of the quadrupole interaction in the 23 Na NMR central line was estimated. The range comprises ionic charges approximately up to the first nearest neighbour Na + site from the 23 Na nucleus, showing a large difference compared with that obtained from the 14 N NQR investigation in the same system. 
  Reference    Z. Naturforsch. 53a, 595—598 (1998); received October 31 1997 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0595.pdf 
 Identifier    ZNA-1998-53a-0595 
 Volume    53 
83Author    Fereidoun Khajenouri, Shahrokh Motallebi, E.A C LückenRequires cookie*
 Title    Cu NQR Studies of Three-coordinated Complexes of Cu(I) with an Isocyanide Ligand  
 Abstract    The 63 Cu NQR spectra of five three-coordinated complexes of Cu(I) containing an isocyanide ligand are reported. The resonance frequencies are compared with those of other three-coordinated Cu(I) com-plexes using a partial coupling constant model to describe the effects of the various ligands and to take into account the effects of variations in the molecular geometries. The partial coupling constant of the isocyanide ligand is much higher than that of any other ligand studied so far and leads to the order of donor atom partial field gradients for terminal ligands C>N>Cl>P = S = Br>I>0. 
  Reference    Z. Naturforsch. 53a, 599—602 (1998); received March 24 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0599.pdf 
 Identifier    ZNA-1998-53a-0599 
 Volume    53 
84Author    Hiroshi Miyoshi, Keizo Horiuchi, Narumi Sakagami, Kenichi Okamoto, Ryuichi IkedaRequires cookie*
 Title    C1 NQR, *H NMR, and X-Ray Diffraction Studies in a Hydrogen Bonded Complex Na 2 PtCl 6 * 6H z O  
 Abstract    The 35 C1 NQR frequencies, spin-lattice relaxation time and X H NMR relaxation time were measured on crystalline Na 2 PtCl 6 • 6H z O at 77-350 K. The presence of three nonequivalent chlo-rine sites found by X-ray diffraction measurement is in agreement with the observed three NQR lines, which have different temperature dependences attributable to differences in the direction of H-bonding with water molecules. The three NQR lines correspond to three kinds of chlorines with different Pt-Cl distances and H-bond directions. 
  Reference    Z. Naturforsch. 53a, 603—607 (1998); received October 31 1997 
  Published    1998 
  Keywords    CI NQR, X-Ray Diffraction, Spin-Lattice Relaxation, Quadrupole Coupling Constant, Hydrogen Bond 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0603.pdf 
 Identifier    ZNA-1998-53a-0603 
 Volume    53 
85Author    M. I. OshtrakhRequires cookie*
 Title    The Features of Mössbauer Spectra of Hemoglobin in Relation to the Quadrupole Splitting and Heme Iron Stereochemistry  
 Abstract    Mössbauer spectra of various human ferrous hemoglobins in different ligand forms demonstrated some features such as non-Lorentzian line shape for oxyhemoglobins, narrower line width for carbonmonoxide, and variations of quadrupole splitting for different hemoglobins. These features were considered in relation to the variations of quadrupole splitting and heme iron stereochemistry in different hemoglobins as well as in non-equivalent subunits of hemoglobin tetramer. 
  Reference    Z. Naturforsch. 53a, 608—614 (1998); received January 26 1998 
  Published    1998 
  Keywords    Mössbauer Spectroscopy, Human Hemoglobins, Quadrupole Splitting, Heme Iron Stereochemistry 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0608.pdf 
 Identifier    ZNA-1998-53a-0608 
 Volume    53 
86Author    MichaelH. PalmerRequires cookie*
 Title    Experimental Gas-phase Halogen Nuclear Quadrupole Coupling Constants; A Review  
 Abstract    As a preclude to a theoretical study of nuclear quadrupole coupling constants (NQCC), via the electric field gradients at equilibrium, we review the current state of knowledge of gas-phase data for a diverse set of axially symmetric inorganic and organic molecules with symmetries C 3v , C oov , D^ in particular, where the heavy elements are CI, Br and I with C, Si and Ge hydrides. In most of the cases, the latter elements are in an approximately tetrahedral environment. 
  Reference    Z. Naturforsch. 53a, 615—619 (1998); received January 8 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0615.pdf 
 Identifier    ZNA-1998-53a-0615 
 Volume    53 
87Author    Y. M. Park, S. K. Song, Y. M. Seo, J. K. Jung, S. H. ChohRequires cookie*
 Title    N NQR Study of Mixed Complexes (NaN0 2 )i_ JC (AN0 3 ) JC : (A=K, Na)  
 Abstract    14 N nuclear quadrupole resonance of the system (NaN0 2)i_ J (AN0 3) A . with A = K and Na in the x-range 0<x<0.5 and the temperature range 77 K<7<360 K has been studied. The l4 N NQR frequen-cy of NaN0 2 and its line width do not change with x, the latter fact untrasting the results of other mixed systems such as Na|_,.Ag v N0 2 . This indicates that in (NaN0 2)!_ v (AN0 3) v highly mobile lattice defects exist. The dependence on x of the rate of change in the spin-lattice relaxation time T x near the transition temperature is discussed in terms of a correlated flipping motion of the N0 2 ion groups. 
  Reference    Z. Naturforsch. 53a, 620—624 (1998); received March 24 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0620.pdf 
 Identifier    ZNA-1998-53a-0620 
 Volume    53 
88Author    Sundara Ramaprabhu, Nahid Amstutz, EdwinA C Lücken, Gerald BernardinelliRequires cookie*
 Title    Cu NQR and Structural Studies of Complexes Formed Between Cu(I) Halides and /ra(o-methoxyphenyl)-or /ra(p-tolyl)phosphine Ligands  
 Abstract    The crystal structure of [tri(o-methoxyphenvl)phosphine] 2 Cu 2 Br 2 shows it to be a halogen-bridged dimer with three-coordinated Cu (I) sites. The Cu NQR frequency of the corresponding chloride indi-cates that it has a similar structure. The 63 Cu NQR frequencies of the complexes of tri(p-tolyl)phos-phine, L 3 Cu 2 X 2 , with cuprous chloride and bromide are consistent with their having halogen-bridged structures with both three-and four-coordinated Cu(I) sites analogous to those formed by triphenyl-phosphine and tri(m-tolyl)phosphine. Cu(I) sites. [CuBr(P(C 7 H v O) 3 ] 2 ; Triclinic, P 1, Z=2, a = 8.969(1), b= 10.510(2), c=l 1.428(2) Ä, a=99.46(l), ß=91.95(\), y= 104.17(1)°, R=3.5%, R^.2%. 
  Reference    Z. Naturforsch. 53a, 625—629 (1998); received March 24 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0625.pdf 
 Identifier    ZNA-1998-53a-0625 
 Volume    53 
89Author    L. G. Shpinkova, V. N. Kulakov, A. A. Sorokin, G. K. Ryasny, B. A. Komissarova, S. M. NikitinRequires cookie*
 Title    Stability of in In-ligand Complexes Studied by TDPAC  
 Abstract    The TDPAC technique has been applied to study the stability of ni In complexes with NTA and DTPA in solutions with different concentrations of stable In at pH = 7. A sample of In-DTPA complexes attached to microspheres of albumin (MSA) has been measured at temperatures of 293 and 130 K. The results show that the products formed after U1 ln -* • ul Cd decay and following Auger-effect are determined by the stability of In (Cd)-complexes with organic ligands. The daugh-ter Cd behaviour depends on the In: ligand mole ratio, from 1: oo to 1:1. The possibility of Cd-ligand complex destruction and following Cd rechelating is discussed. The results indicate that the rechelating probability correlates with the stability of the parent and daughter complexes. PACS: 36, 82, 87. 
  Reference    Z. Naturforsch. 53a, 630—635 (1998); received October 31 1997 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0630.pdf 
 Identifier    ZNA-1998-53a-0630 
 Volume    53 
90Author    F. H. FröhnerRequires cookie*
 Title    Missing Link Between Probability Theory and Quantum Mechanics: the Riesz-Fejer Theorem  
 Abstract    Quantum mechanics is spectacularly successful on the technical level but the meaning of its rules remains shrouded in mystery even more than seventy years after its inception. Quantum-mechanical probabilities are often considered as fundamentally different from classical probabilities, in disre-gard of the work of Cox (1946) -and of Schrödinger (1947) -on the foundations of probability theory. One central question concerns the superposition principle, i. e. the need to work with inter-fering wave functions, the absolute squares of which are probabilities. Other questions concern the relationship between spin and statistics or the collapse of the wave function when new data become available. These questions are reconsidered from the Bayesian point of view. The superposition principle is found to be a consequence of an apparently little-loiown mathematical theorem for non-negative Fourier polynomials published by Fejer in 1915 that implies wave-mechanical inter-ference already for classical probabilities. Combined with the classical Hamiltonian equations for free and accelerated motion, gauge invariance and particle indistinguishability, it yields all basic quantum features -wave-particle duality, operator calculus, uncertainty relations, Schrödinger equation, CPT invariance and even the spin-statistics relationship -which demystifies quantum mechanics to quite some extent. 
  Reference    Z. Naturforsch. 53a, 637—654 (1998); received January 28 1998 
  Published    1998 
  Keywords    Superposition Principle, Wave Packets, Logical Inference, Wave-Particle Duality, Quantum Mechanics 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0637.pdf 
 Identifier    ZNA-1998-53a-0637 
 Volume    53 
91Author    Masanori Sakurai, Ryuzo Takagi, AshokK. Adya, Marcelle Gaune-EscardRequires cookie*
 Title    Estimation of the Chemical Potential and the Activity of NaCl in Molten DyCl 3 -NaCl by Molecular Dynamics Simulation  
 Abstract    Molecular dynamics simulations of molten DyCl 3 -NaCl were carried out at liquidus temperatures of the phase diagram. The chemical potential and the activity of NaCl was successfully estimated with the method proposed by Powles et al., which requires only positional data of the ions at the temperatures in question. 
  Reference    Z. Naturforsch. 53a, 655—658 (1998); received April 18 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0655.pdf 
 Identifier    ZNA-1998-53a-0655 
 Volume    53 
92Author    F. WinterbergRequires cookie*
 Title    Conjectured Breaking of the Superluminal Quantum Correlations By Türbulent Fluctuations of the Zero Point Vacuum Field  
 Abstract    If the observed superluminal quantum correlations are disturbed by turbulent fluctuations of the ze-ro point vacuum energy field, with the turbulent energy spectrum assumed to obey the universal Kol-mogoroff law, a length is derived above which the correlations are conjectured to break. A directional dependence of this length would establish a preferred reference system at rest with the zero point ener-gy. Assuming that the degree of turbulence is given by the small anisotropy of the cosmic microwave background radiation, a length of -60 km is derived above which the correlations would break. 
  Reference    Z. Naturforsch. 53a, 659—662 (1998); received October 20 1997 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0659.pdf 
 Identifier    ZNA-1998-53a-0659 
 Volume    53 
93Author    H. MayerRequires cookie*
 Title    Reflection of Cluster Beams on Metal Surfaces: Momentum and Heat Transfer  
 Abstract    Beams of clusters, the latter containing about 10 6 nitrogen molecules, were reflected by polished met-al surfaces, and the direction, the velocity and the composition of the reflected beams were studied as functions of the direction of the incident beam. It turned out that the clusters leave the reflector surface almost tangentially, with reduced velocity, and that besides the clusters the beams contain gaseous ni-trogen formed during the impact. 
  Reference    Z. Naturforsch. 53a, 663—669 (1998); received March 8 1998 
  Published    1998 
  Keywords    Cluster Beams, Molecular Beams, Beam Surface Interaction, Cluster Reflection, Heat Transfer 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0663.pdf 
 Identifier    ZNA-1998-53a-0663 
 Volume    53 
94Author    N., M. Pfeffer, W. Bodenmüller, A. RuoffRequires cookie*
 Title    FT-IR Study of the Perpendicular Bands of 1,3,5-Triazine I:* The v 7 and v 9 Bands of 12 C 3 14 N 3 H 3 , 13 C 3 14 N 3 H 3 , 12 C 3 15 N 3 H 3 and the Difference Band v 9 -v 14 of 12 C 3 14  
 Abstract    The analysis of the high resolution FT-IR spectra of the perpendicular bands v 7 (£") at about 1550 cm -1 and V 9 (£") at about 1170 cm -1 of the isotopomers 12 C 3 N 3 H 3 , 13 C 3 14 N 3 H 3 , and l2 C 3 I5 N 3 H 3 is given. Both bands proved to be free from accidental resonances. The molecular constants of the state v-, = 1 and v 9 = 1 of the isotopomers under consideration are listed. The weak difference band v 9 -v l4 (E" —> E') of 12 C 3 14 N 3 H 3 was recorded and analyzed, using the molecular constants of v 9 = 1 [this work] and V\4 = 1 [of 1995], This analysis proves the quality of the molecular constants of the fundamental v 14 which is IR-inactive. 
  Reference    Z. Naturforsch. 53a, 670—678 (1998); received March 31 1998 
  Published    1998 
  Keywords    High Resolution FT-IR Spectroscopy, l,3,5-Triazine,PerpendicularBand, DifferenceBand 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0670.pdf 
 Identifier    ZNA-1998-53a-0670 
 Volume    53 
95Author    Y. Waseda, S. Suzuki, K. UrbanRequires cookie*
 Title    Novel Morphology of Voids in Single-Quasicrystalline Icosahedral Al ?0 5 Pd 210 Mn 8 5  
 Abstract    This paper deals with the morphology and surface chemistry of faceted voids existing in single-quasicrystalline icosahedral Al 70 5 Pd 2 i. 0 Mn 8 5 . By observation with a scanning electron microscope of surfaces obtained by cleavage of the quasicrystal, the habit planes of the dodecahedral voids were identified. The chemical surface composition of the void surface was determined by Auger electron spectroscopy after cleavage in ultra-high vacuum. 
  Reference    Z. Naturforsch. 53a, 679—683 (1998); received December 29 1997 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0679.pdf 
 Identifier    ZNA-1998-53a-0679 
 Volume    53 
96Author    J. Heidt, J. R. Heidt, M. RaciniewskaRequires cookie*
 Title    Experimental Determination of Dipole Moments of Some Benzamide Derivatives  
 Abstract    The excited state dipole moments of some benzamide derivatives are determined. The method of sol-vent induced shifts of electronic absorption bands in comparison with their positions in the gas phase is used. Some regular trends revealed in the obtained data are discussed. The present results are com-pared with those available in the literature. 
  Reference    Z. Naturforsch. 53a, 684—688 (1998); received May 15 1998 
  Published    1998 
  Keywords    Benzamides, Absorption Spectra, Dipole Moments 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0684.pdf 
 Identifier    ZNA-1998-53a-0684 
 Volume    53 
97Author    Li-Li Chen, Sen-Yue LouRequires cookie*
 Title    Higher Dimensional Integrable Models with Painleve Property Obtained from (l+l)-Dimensional Schwarz KdV Equation  
 Abstract    Using the extended Painleve analysis, we obtained some higher dimensional integrable models with the Painleve property from the (l+l)-dimensional Schwarz KdV equation. 
  Reference    Z. Naturforsch. 53a, 689—692 (1998); received March 24 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0689.pdf 
 Identifier    ZNA-1998-53a-0689 
 Volume    53 
98Author    C. B. Azzoni, M. C. Mozzati, A. Paleari, V. Massarotti, D. Capsoni, M. BiniRequires cookie*
 Title    Magnetic Order in Li-Mn Spinels  
 Abstract    Magnetic measurements were carried out on different samples of Lithium-Manganese spinel LiMn 2 0 4 , great care having been taken to avoid the presence of spurious magnetic phases, such as Mn 3 0 4 . Sus-ceptibility data, showing deviations from paramagnetic behaviour at about 40 K, were analyzed in terms of local magnetic interactions, taking into account the structural and transport properties of these com-pounds. The magnetic response of pure and stoichiometric samples suggests that the onset of a long-range magnetic ordering is hindered by the topological frustration of the antiferromagnetic octahedral sublattice of the spinel. 
  Reference    Z. Naturforsch. 53a, 693—698 (1998); received April 25 1998 
  Published    1998 
  Keywords    Magnetic Susceptibility, Electron Paramagnetic Resonance, Lithium Manganese Oxides, Lithium Manganese Spinel 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0693.pdf 
 Identifier    ZNA-1998-53a-0693 
 Volume    53 
99Author    Ivan Gutman, SvenJ. Cyvin, Vesna Ivanov-PetrovićRequires cookie*
 Title    Topological Properties of Circumcoronenes  
 Abstract    The regular-hexagon-shaped benzenoid hydrocarbons: B, = benzene (C 6 H 6), B 2 = coronene (C24H12), B 3 = circumcoronene (C 54 H 18), B 4 = circumcircumcoronene (C 15 oH 3 o), etc. possess unique topological properties. General expressions for the most important of such properties (number of fun-damental structural invariants, number of Kekule and Clar structures, number of aromatic sextets, Wie-ner and Szeged indices, spectral moments) are given, including a number of results that are communi-cated here for the first time. Cyclic conjugation in circumcoronenes is analyzed by means of its ener-gy-effect, and found to agree with the predictions of Clar's aromatic sextet theory only in the case of B[ and B 2 . 
  Reference    Z. Naturforsch. 53a, 699—703 (1998); received April 4 1998 
  Published    1998 
  Keywords    Circumcoronenes, Benzenoid Hydrocarbons, Topological Properties (of Benzenoid Hydro-carbons), Kekule Structures, Clar Theory 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0699.pdf 
 Identifier    ZNA-1998-53a-0699 
 Volume    53 
100Author    Jörg Fleischhauer, Christoph Jansen, Axel Koslowski, Gerhard Raabe, Jan Schiffer, Axel WollmerRequires cookie*
 Title    Determination of the Absolute Configuration of Bis(tetrahydropyran- 2-yl)methane by Comparison of Measured and Calculated CD-spectra  
 Abstract    The absolute configuration of bis(tetrahydropyran-2-yl)methane (1) was determined by compar-ison of measured and calculated CD spectra. The theoretical CD spectra were obtained by means of the CNDO/2S method. The five presum-ably lowest local minima on the energy hypersurface of the title compound were used to describe the conformer equilibrium mixture. The geometries of these conformers were calculated employing the MM3 force field, the semiempirical AMI method and one-determinant ab initio calculations employing the 6-31G* basis set. Boltzmann factors were then obtained using relative energies cal-culated with three different basis sets and including correlation-and zero point vibrational energy. Based on the sign of the observed and calculated longest wavelength Cotton effect we assign an absolute configuration to the compound which is in keeping with the chirality expected from the assumed reaction mechanism. The results of force field and ab initio calculations converge to the point that the conformer equilibrium is dominated (85 -96%) by one single conformer which is energetically separated from the other conformers by about 2-3 kcal/mol. This result agrees with previous experimental data. 
  Reference    Z. Naturforsch. 53a, 704—710 (1998); received May 18 1998 
  Published    1998 
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 TEI-XML for    default:Reihe_A/53/ZNA-1998-53a-0704.pdf 
 Identifier    ZNA-1998-53a-0704 
 Volume    53 
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