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1997[X]
81Author    Ryuzi Katoh, Klaus Lacmann, WernerF. SchmidtRequires cookie*
 Title    Photoconductivity of an Anthracene / 2,2,4,4-Tetramethylpentane Solution: Pressure Effect on the Photoionization of Solute and Solvent  
 Abstract    The photoconductivity spectrum of a solution of anthracene (AN) in 2,2,4,4-tetramethylpentane (TMP) was measured as a function of pressure up to 2 kbar. The threshold energies of photoion-ization of the solute (AN) and of the solvent (TMP) increase with pressure. The relative quantum yield for charge carrier generation decreased with increasing pressure. The concomitant reduction of the initial separation distance of the geminate charge carrier pairs may be due to an increase of the number of inelastic collisions caused by the increased density of the liquid within the sphere of Coulomb attraction of the positive ion. 
  Reference    Z. Naturforsch. 52a, 435—440 (1997); received December 18 1996 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0435.pdf 
 Identifier    ZNA-1997-52a-0435 
 Volume    52 
82Author    P.-H Chou, I. OkadaRequires cookie*
 Title    Internal Mobilities in the Molten Binary Systems (Tl, K)N0 3 and (Tl, Cs)N0 3  
 Abstract    Ratios of internal cation mobilities in the molten binary systems (Tl, K)NO a and (Tl, Cs)N0 3 have been measured by the Klemm method. From these and the data available on the densities and electric conductivities, the internal mobilities b have been calculated. While generally in the mixtures of T1N0 3 with alkali nitrates at constant temperature the conductivities and internal mobilities decrease with increasing molar volume, in (Tl, K)N0 3 they decrease with decreasing molar volume. This is explained by the high polarizability of the Tl + ions. 
  Reference    Z. Naturforsch. 52a, 441—446 (1997); received March 3 1996 
  Published    1997 
  Keywords    Internal mobility, Klemm method, molten (Tl, K)N0 3, molten (Tl, Cs)N0 3, high polar-izability 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0441.pdf 
 Identifier    ZNA-1997-52a-0441 
 Volume    52 
83Author    Ingo Biertümpel, Hans-Herbert SchmidtkeRequires cookie*
 Title    Evaluation of Luminescence Decay Measurements Probed on Pure and Doped Pt(IV) Hexahalogeno Complexes. II. Molecular Properties Obtained from Temperature Dependent Lifetime Curves  
 Abstract    Lifetime measurements down to nearly liquid helium temperatures are used for determining energy levels and transition rates between excited levels and relaxations into the ground state. Energies are obtained from temperature dependent lifetimes by fitting experimental curves to model functions pertinent for thermally activated processes. Rates are calculated from solutions of rate equations. Similar parameters for pure and doped Pt(IV) hexahalogeno complexes indicate that excited levels largely belong to molecular units. Some of the rates between excited states are only somewhat larger than decay rates into the ground state, which is a consequence of the polyexponential decay measured also at low temperature (2 K). In the series of halogen complexes, the rates between spinorbit levels resulting from 3 Ti g increase from fluorine to bromine, although energy splittings become larger. Due to the decreasing population of higher excited states in this series, K^PtFö shows a tri-exponential, K^PtClö a bi-exponential and FoPtBre a mono-exponential decay. In the latter case the population density of higher excited states relaxes so fast that emission occurs primarily from the lowest excited F}(3 Ti 9) level. Phase transitions and emission from chromophores on different sites can also be observed. 
  Reference    Z. Naturforsch. 52a, 447—456 (1997); received January 22 1997 
  Published    1997 
  Keywords    Pt(IV) complexes, luminescence decay, temperature dependence 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0447.pdf 
 Identifier    ZNA-1997-52a-0447 
 Volume    52 
84Author    Sn Bakalova, A. Georgieva, P. Nikolov, E. StanoevaRequires cookie*
 Title    Dihydronaphthalenone Carboxylates - Spectral Characteristics and Structure  
 Abstract    The absorption and luminescence characteristics of a group of newly synthesized methyl esters of 2-alkyl (p-substituted-aryl) -aminomethylene-3,4-dihydro-l(2 H)-naphthalenone-4-carboxylic acids have been investigated. The studied compounds may exist in three tautomeric forms. On the basis of comparison of their electronic spectra to those of similar substances, the observed substituent effect on the position of the UV-VIS absorption bands, the IR spectra and the results of PPP-SCF-CI quantum-chemical calculations it is concluded that the keto tautomer predominates in solution. 
  Reference    Z. Naturforsch. 52a, 457—461 (1997); received December 31 1996 
  Published    1997 
  Keywords    Electronic spectra, Tautomerism, Dihydronaphthalenone carboxylates 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0457.pdf 
 Identifier    ZNA-1997-52a-0457 
 Volume    52 
85Author    Bo Tian, Yi-Tian GaoRequires cookie*
 Title    Report on the Generalized Tanh Method Extended to a Variable-Coefficient Korteweg- de Vries Equation  
 Abstract    We briefly report that the generalized tanh method can be extended from the situation with coefficient constants to that with coefficient functions. Soliton-typed solutions for a vari-able-coefficient Korteweg-de Vries equation are thus found. Similar work can be done for the generalized variable-coeffi-cient Kadomtsev-Petviashvili equations. 
  Reference    Z. Naturforsch. 52a, 462 (1997); received February 7 1997 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0462_n.pdf 
 Identifier    ZNA-1997-52a-0462_n 
 Volume    52 
86Author    Bo TianRequires cookie*
 Title    Research Note on New Similarity Reductions of a Variable-Coefficient Korteweg-de Vries Equation  
 Abstract    For a variable-coefficient Korteweg-de Vries equation we obtain 4 new similarity reductions to the Painleve type equa-tions or the Weierstrass elliptic function equation. 
  Reference    Z. Naturforsch. 52a, 463—464 (1997); received February 7 1997 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0463_n.pdf 
 Identifier    ZNA-1997-52a-0463_n 
 Volume    52 
87Author    Valerie Bertagna, Francis Rouelle, Marius ChemlaRequires cookie*
 Title    Copper Contamination Mechanism of Silicon Substrates from HF Solutions  
 Abstract    The contamination of silicon wafers from dilute HF solutions containing ultratrace levels of metallic ion impurities is a subject of constant interest. The mechanism of copper electroless deposition from HF onto monocrystalline silicon was investigated using a new electrochemical cell, which proved to be a very sensitive detector for in situ characterization of silicon surfaces. Upon addition of copper trace amounts, the open-circuit potential was observed to shift rapidly towards more positive values at a rate nearly proportional to the copper concentration. All poten-tial/time curves tend to reach a limiting value of the potential, while quantitative measurements of radioactive tracers revealed that during a few tens of minutes, copper ions were continuously reduced on the silicon surface. Electrochemical potentials and voltammetric measurements were interpreted in terms of the mixed potential theory and led to the conclusion that copper nuclei act as a catalyst which enhances the cathodic activity for protons reduction. The model was supported by AFM observations which demonstrated the initiation of corrosion pits around the nuclei. 
  Reference    Z. Naturforsch. 52a, 465—176 (1997); received April 14 1997 
  Published    1997 
  Keywords    Silicon, contamination, copper, catalysis 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0465.pdf 
 Identifier    ZNA-1997-52a-0465 
 Volume    52 
88Author    Roman GocRequires cookie*
 Title    Calculation of the NMR Second Moment for Solid Benzene with Rotation and Diffusion of Molecules -Numerical Approach  
 Abstract    Numerical calculations of the NMR second moment in case of rotation and diffusion of molecules were performed. As an example computer simulations of molecular reorientation and self-diffusion in solid benzene have been performed. For each model and rate of motion the Van Vleck's second moment of the proton NMR absorption spectrum was calculated, and these values were compared with experimental data. It is concluded that restricted self-diffusion must be implied in order to obtain better agreement between calculated and experimental NMR second moments. The temperature at which self-diffusion was detected through NMR line-width narrowing was found to be about 120 K, nearly 80 K less than the temperature at which the self-diffusion was detected by T lp relaxation measurements. 
  Reference    Z. Naturforsch. 52a, 477—184 (1997); received March 29 1997 
  Published    1997 
  Keywords    NMR, molecular rotation, self-diffusion, numerical approach 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0477.pdf 
 Identifier    ZNA-1997-52a-0477 
 Volume    52 
89Author    N. Horasan, M. M. Sünnetçioğlu, R. Sungur, G. BingölRequires cookie*
 Title    A Weak Field EPR Study of TANOL in Water and Water-Oil Using Dynamic Nuclear Polarization  
 Abstract    Solutions of 4-hydroxy-TEMPO(TANOL) in water and water-soyabean oil were investigated in the concentration range 0.1 mM-10mM. Dynamic nuclear polarization (DNP) and electronic relaxation time T le measurements were performed at each well resolved hyperfine line. In the TANOL/water-soyabean oil solutions, the effect of the presence of soyabean oil was an increase in the measured relaxation rates and a decrease in the observed enhancements. In addition, the observed enhancements diminished in time. For all of the samples, the relaxation rates decreased as the frequency of the transition increased. 
  Reference    Z. Naturforsch. 52a, 485—489 (1997); received January 29 1997 
  Published    1997 
  Keywords    DNP, EPR, Nitroxides, Electronic relaxation times, Water-Oil 
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 Identifier    ZNA-1997-52a-0485 
 Volume    52 
90Author    C. Ernst, G. M. Schneider, A. Würflinger, J. Jadżyn, R. DąbrowskiRequires cookie*
 Title    Differential Thermal Analysis under High Pressure on 6-TPEB  
 Abstract    The high pressure phase behaviour of a new liquid crystal, belonging to the series l-[4-«-alkyl-biphenyl]-2-[4-isothio-cyanato-phenyl] ethane (/iTPEB), n = 6, has been studied with differential thermal analysis. The pressure dependence of the phase transitions has been determined up to 300 MPa. No pressure-induced or pressure-limited phases are observed in this pressure range, the phase behaviour, however, depends on the thermal treatment. Enthalpy and volume changes accom-panying the phase transitions have been calculated using the Clausius-Clapeyron equation. 
  Reference    Z. Naturforsch. 52a, 490—492 (1997); received March 23 1997 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0490.pdf 
 Identifier    ZNA-1997-52a-0490 
 Volume    52 
91Author    M. Jenau, M. Sandmann, A. Würflinger, J.Li TamaritRequires cookie*
 Title    Differential Thermal Analysis and PVT Measurements on 2,2,2-Trichloro-ethanol Under High Pressure  
 Abstract    The phase behaviour, the calorimetric and volumetric properties of 2,2,2-trichloro-ethanol (TCE) have been studied with differential thermal analysis (DTA) and pVT measurements in the pressure range 1 atm to 300 MPa and temperatures between 250 K to 355 K. TCE displays a metastable plastic phase (solid I') and a non-plastic solid phase II at atmospheric pressure. At least two pressure-induced solid phases have been detected: a stable plastic phase (solid I) and a non-plastic phase (solid III). There are two sets of triple points: a) 123 MPa and 308 K with the phases solid I, solid II and the liquid, b) 243 MPa and 316 K for solid I, II, III. Furthermore a metastable low-temperature brittle form (solid II') has been found, which transforms to solid I at a considerably lower temperature than solid II. The melting curve of solid I' can be pursued to higher pressures up to 260 MPa. On the other hand, the melting curve of the stable plastic phase solid I can be extrapolated beyond the triple point to pressures below 123 MPa. Volume and enthalpy changes are reported for all phase transitions. 
  Reference    Z. Naturforsch. 52a, 493—501 (1997); received April 26 1997 
  Published    1997 
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 Identifier    ZNA-1997-52a-0493 
 Volume    52 
92Author    Takahiro Ueda, Mariko Omo, Katsuyuki Shimizu, Hiroshi Ohki, Tsutomu OkudaRequires cookie*
 Title    Ionic Motion of Phenethylammonium Ion in [C 6 H 5 CH 2 CH 2 NH 3 ] 2 PbX 4 (X = C1, Br, I) as Studied by l H NMR  
 Abstract    The temperature dependences at 110 to 400 K of the : H spin-lattice relaxation time (7\) of the phenethylammonium ion in phenethylammonium lead(II) halides, [C 6 H 5 CH 2 CH 2 NH 3 ] 2 PbX 4 (X = C1, Br, I), revealed that this ion shows reorientation of the NH 3 moiety around the three-fold axis and torsional motion of the alkyl chain (CH 2 CH 2). Below room temperature, the chloride and the bromide yielded two minima of *H T l originating from NH 3 reorientation, whereas the iodide yielded only one minimum. These findings indicate that there are two kinds of NH 3 sites in the chloride and bromide but only one in the iodide. The 7\ minimum observed below room tempera-ture gave similar activation energies of the NH 3 reorientation, £ a = 15.7,15.1 and 15.5 kJ mol" 1 for the chloride, bromide and iodide, respectively, suggesting that the corresponding NH 3 groups are located at similar environments. Above room temperature, the 7\ minimum in the chloride and bromide gave larger E a values of the NH 3 reorientation: E a — 23.6 and 20.2 kJ mol" 1 for the chloride and bromide, respectively. These findings suggest that the NH 3 groups form stronger hydrogen bonding with halogen atoms (N-H ... X). Furthermore, the amplitude of the CH 2 CH 2 motion is discussed, using the two sites jump model. The activation energies for the CH 2 CH 2 motion in these compounds are almost equal (E a = 29.1, 30.0 and 28.2 kJ mol" 1 for the chloride, bromide and iodide, respectively), but that the torsional angles become larger in the order iodides bromide < chloride. 
  Reference    Z. Naturforsch. 52a, 502—508 (1997); received April 8 1997 
  Published    1997 
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 Identifier    ZNA-1997-52a-0502 
 Volume    52 
93Author    K. A. Schindler, C. A. Bernasconi, R. Stoop, P. H. Goodman, R. J. DouglasRequires cookie*
 Title    Chaotic Spike Patterns Evoked by Periodic Inhibition of Rat Cortical Neurons  
 Abstract    We use methods of nonlinear dynamics to describe the effect of periodic inhibition on the patterns of action potentials generated by regular spiking rat cortical neuron in vitro. Both direct measure-ments and our mathematical model reveal that chaotic patterns of discharge can be evoked at certain frequencies of inhibitory stimulation. We use detailed biophysical simulation of a cortical neuron to explain the firing patterns in terms of known membrane ionic conductances. 
  Reference    Z. Naturforsch. 52a, 509—512 (1997); received May 13 1997 
  Published    1997 
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 Identifier    ZNA-1997-52a-0509 
 Volume    52 
94Author    Takashi Tsuchiya, Daisuke YamagishiRequires cookie*
 Title    The Complete Bifurcation Diagram for the Logistic Map  
 Abstract    The complete bifurcation diagram as well as the basin of attraction for the logistic map is presented for the whole range of the control parameters, namely —2<a<4 where the system remains finite. Equivalence of the newly found bifurcation branch to the conventional branch is shown. 
  Reference    Z. Naturforsch. 52a, 513—516 (1997); received February 11 1997 
  Published    1997 
  Keywords    Logistic map, bifurcation diagram, basin of attraction, equivalent transformation 
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 Identifier    ZNA-1997-52a-0513 
 Volume    52 
95Author    Z. A. Fokina, V. L. Kolesnichenko, V. L. Pekhnyo, S. V. VolkovRequires cookie*
 Title    Peculiarities of the 35 C1 and 79 Br NQR Spectra of Chalcogenhalide Complexes of Some Transition Metals  
 Abstract    The peculiarities of the 35 C1, 79 Br NQR spectra of the chalcogenhalide complexes are explained in terms of intraspheric effect of ligands, formation of secondary intra-and intermolecular bonds, and electronic structure of metal atom. In the 35 C1 spectra of [reCl 3 ] 2 [OsCl 6 ] 1, [SeCl 3 ] 2 [OsCl 6 ]2 and [TeCl 3 ] 2 [ReCl 6 ]3 the 7-10% increase in frequency in the low-frequency multiplet are accounted for by the disturbance of the p Ha rd M ^-interaction due to the formation of the peripheral coordination polyhedra [SeCl 6 ] and [TeCl 6 ]. The peculiarities of the 35 C1 and 79 Br spectra of [MoS 2 Cl 3 (SeCl 2)] 2 4, [MoS 2 Br 3 (SeCl 2)] 2 5, [WS 2 Cl 3 (SeCl 2)] 2 6 and [WS 2 Br 3 (SeBr 2)] 2 7 are attributed to the disturbance of the PHar^M ^-interaction under the influence of the coordination of the SeCl 2 and SeBr 2 ligands and formation of secondary intramolecular bonds. For [RhCl 3 (SeCl 2) 2 ] 2 8, [IrCl 3 (SeCl 2) 2 ] 2 9 and [SCl 3 ][IrCl 4 (SCl 2) 2 ]10, the appearance of frequencies at 25 MHz in low-frequency triplets is attrib-uted to the intraspheric effect of weak donors-neutral SC1 2 and SeCl 2 molecules; the frequencies at 18 MHz are assigned to bridging chlorine atoms. This assignment was confirmed by the dimeric structure, which was established by an X-ray structure analysis. Key words: Molybdenum (V), tungsten (V), rhenium (IV), osmium (IV), rhodium (III), iridium (III), electronic structure. 
  Reference    Z. Naturforsch. 52a, 517—520 (1997); received January 27 1997 
  Published    1997 
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 Identifier    ZNA-1997-52a-0517 
 Volume    52 
96Author    Toshiyuki Takamuku, Motoyuki Yamagami, Hisanobu Wakita, Toshio YamaguchiRequires cookie*
 Title    X-ray Diffraction Studies on Supercooled Aqueous Lithium Bromide and Lithium Iodide Solutions  
 Abstract    X-ray diffraction measurements were performed on liquid LiBr • 5H 2 0 and Lil • 5H 2 0 at tem-peratures from —30 to 25 °C. The total radial distribution functions did show that on supercooling the hydration shell of the halide ions becomes more structured, while that of the lithium ions becomes distorted. The larger the halide ion, the stronger becomes the water-water interaction around halide ions with lowering temperature. However, the distance between the water molecules in the hydration shells of the halide ions depends little on their size. On the basis of the present results, together with those of our previous investigation on LiCl • 5H 2 0 at temperatures from — 135 to 100°C, the effects of temperature and the size of the halide ions on the structure of the solution are discussed. 
  Reference    Z. Naturforsch. 52a, 521—527 (1997); received March 13 1997 
  Published    1997 
  Keywords    Lithium Bromide, Lithium Iodide, X-ray diffraction, Supercooled temperature, Hydra-tion structure 
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 Identifier    ZNA-1997-52a-0521 
 Volume    52 
97Author    R. C. Sharma, P. KumarRequires cookie*
 Title    Hydromagnetic Stability of Two Rivlin-Ericksen Elastico-Viscous Superposed Conducting Fluids  
 Abstract    The stability of the plane interface separating two Rivlin-Ericksen elastico-viscous superposed fluids of uniform densities when the whole system is immersed in a uniform horizontal magnetic field has been studied. The stability analysis has been carried out, for mathematical simplicity, for two highly viscous fluids of equal kinematic viscosities and equal kinematic viscoelasticities. It is found that the stability criterion is independent of the effects of viscosity and viscoelasticity and is dependent on the orientation and magnitude of the magnetic field. The magnetic field is found to stabilize a certain wave-number range of the unstable configuration. The behaviour of growth rates with respect to kinematic viscosity and kinematic viscoelasticity parameters are examined numeri-cally. 
  Reference    Z. Naturforsch. 52a, 528—532 (1997); received April 18 1996 
  Published    1997 
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 Identifier    ZNA-1997-52a-0528 
 Volume    52 
98Author    Lon BeckerRequires cookie*
 Title    On the Supposed Surrealism of Bohmian Mechanics  
 Abstract    In a recent paper, Englert et al. reject Bohm's reinterpretation of quantum mechanics as "surreal-istic." Responses to this by Dewdney et al. and Durr et al. have generally missed the point of this somewhat strange characterization of the interpretation. In this paper I explain the experiment which is supposed to illustrate the surrealism. I argue that what is really being objected to is the non-locality of the interpretation. While this is an undesirable feature of Bohm's interpretation, it is not a feature of which the standard interpretation gives a more satisfactory account. 
  Reference    Z. Naturforsch. 52a, 533—538 (1997); received October 26 1996 
  Published    1997 
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 Identifier    ZNA-1997-52a-0533 
 Volume    52 
99Author    Giacomo Cao, Giorgio Concas, Anna Corrias, Roberto Orru ', Giorgio Paschina, Barbara Simoncini, Giorgio SpanoRequires cookie*
 Title    Investigation of the Reaction between Fe 2 0 3 and Al Accomplished by Ball Milling and Self-Propagating High-Temperature Techniques  
 Abstract    In this work we investigate the mechanism of product formation of the aluminothermic reaction of Fe 2 0 3 in the presence of A1 2 0 3 using Ball Milling and Self-propagating High-temperature techniques. Results obtained by experiments under either argon or air atmosphere are analysed by X-ray diffraction and Mössbauer spectroscopy, together with microstructure observations. It is shown that ball milling products are strongly affected by the kind of atmosphere, while self-propagating high-temperature ones are only weakly influenced. Reaction mechanisms taking place in these cases are proposed. While ball milling involves only solid state reactions, the formation of a melt occurs under self-propagating high-temperature conditions. 
  Reference    Z. Naturforsch. 52a, 539—549 (1997); received April 25 1997 
  Published    1997 
  Keywords    Aluminothermic reduction, Ball Milling, Self-propagating High-temperature Synthesis, Mössbauer spectroscopy, X-ray diffraction, Mechanism of reaction 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0539.pdf 
 Identifier    ZNA-1997-52a-0539 
 Volume    52 
100Author    Hideta Ishihara, Shi-Qi Dou, Keizo Horiuchi, Helmut Paulus, Hartmut Fuess, Alarich Weiss, Fachbereich Materialwissenschaft, Fachgebiet StrukturforschungRequires cookie*
 Title    Isolated versus Condensed Anion Structure III: The Influence of the Cations 1,3-propanediammonium, 1,4-butanediammonium, /t-propylammonium, /i-butylammonium and /i-pentylammonium on Structures and Phase Transitions of ZnBrJ" Salts. A 81 Br NQR and X-ray Structure Analysis  
 Abstract    The influence of the cations on the condensation of the anions in the salts (A')Zn(II) Br 4 and (A) 2 Zn(II)Br 4 is studied by 81 Br NQR and X-ray crystal structure analysis. (A')Zn(II)Br 4 (A' = [H 3 N(CH 2) 3 NH 3 ] 2 +) (1) shows a phase transition at 474 K. The phase II of (1) crystallizes with isolated [ZnBrJ 2 " tetrahedra: monoclinic P2 t /«, Z = 4, a = 1108.4 (5), b = 1096.8 (2), c = 1118.5 (6) pm, and ß= 117.07(4)° at 296 K. A quartet was observed in the 81 Br NQR spectrum of phase II: 61.. (A) 2 ZnBr 4 (A = [«-H 3 C(CH 2) 2 NH 3 ] + (2) and [«-H 3 C(CH 2) 3 NH 3 ] + (3)) also show structures with isolated [ZnBrJ 2-tetrahedra. The compound (2) crystallizes with P2Jc, Z = 4, a = 771.8(3), 6 = 1061.9(4), c = 2054.2 (7) pm, and /?= 106.75(1)° at 291 K. The compound (3) crystallizes with P2j/c, Z = 4, a = 768.9(4), 6 = 2229.6(10), c = 1071.6(5) pm, and 0 = 91.70(3)° at 295 K. 81 Br NQR and DSC measurements on [H 3 N(CH 2) 4 NH 3 ]ZnBr 4 (4), and [n-H 3 C(CH 2) 4 NH 3 ] 2 ZnBr 4 (5) were also performed. The compound (4) shows several phase transitions at 349 K and higher tempera-tures, and a quartet in the 81 Br NQR spectrum could be observed between 77 and 330 K: 65.. The compound (5) shows also a phase transition at 244 K, and a quartet of 8 'Br lines could be observed in the NQR spectrum between 77 and 244 K: 61.. The various influences of the cations, such as size and hydrogen bonds on the condensation of [MXJ 2-(M = Zn, Cd; X = C1, Br) are discussed. 
  Reference    Z. Naturforsch. 52a, 550—560 (1997); received March 12 1997 
  Published    1997 
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 TEI-XML for    default:Reihe_A/52/ZNA-1997-52a-0550.pdf 
 Identifier    ZNA-1997-52a-0550 
 Volume    52 
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