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1	Author	W. Sitte, W. Weppner	Requires cookie*
	Title	Electrochemical Investigation of the Ternary Phase Diagram Lithium-Indium-Antimony at 400 °C
	Abstract	The phase diagram of the ternary system Li-In-Sb is determined at 400 °C by electrochemi-cal techniques. The lithium content of samples with different In : Sb ratios is varied by coulomet-ric titration. The equilibrium lithium activities are obtained from emf measurements. Two new ternary compounds, Li 3 InSb 2 and Li 6 InSb 3 with a wide range of stoichiometry, exist along the quasibinary cut InSb-Li 3 Sb. Both compounds are in equilibrium with In and Sb. Li 3 Sb co-exists with all Li-In phases. Semiconducting phases of narrow ranges of stoichiometry show generally fast chemical diffusion rates. The In rich phases have large stoichiometric widths and equilibrate much more slowly.
	Reference	Z. Naturforsch. 42a, 1—6 (1987); received October 1 1986
	Published	1987
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	Identifier	ZNA-1987-42a-0001
	Volume	42

2	Author	A. Müller, E. Bühler, P. Lamparter, S. Steeb	Requires cookie*
	Title	Neutron-and X-ray-Diffraction Study on the Structure of Amorphous Co 25 Ti 75
	Abstract	Amorphous Co 25 Ti 7 5 could be produced using the melt-spin-technique. A neutron-and a X-ray-diffraction experiment was performed. Assuming S NC = 0 the partial Bhatia Thornton structure factors S NN and S C q as well as the partial coordination numbers were calculated. The discussion yields the atomic distances and the chemical short range order parameters.
	Reference	Z. Naturforsch. 42a, 7—12 (1987); received October 14 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0007.pdf
	Identifier	ZNA-1987-42a-0007
	Volume	42

3	Author	B. S. Dandapat	Requires cookie*
	Title	Finite Amplitude Convection in a Rotating Porous Medium
	Abstract	The onset of convection in a horizontal layer of a saturated porous medium heated from below and rotating about a vertical axis with uniform angular velocity is investigated. It is shown that when S e a> 1, overstability cannot occur, where e is the porosity, a the Prandtl number and 5 is related to the heat capacities of the solid and the interstitial fluid. It is also shown that for small values of the rotation parameter T\, finite amplitude motion with subcritical values of Rayleigh number R (i.e. R < R c , where R c is the critical Rayleigh number according to linear stability theory) is possible. For large values of T\, overstability is the preferred mode.
	Reference	Z. Naturforsch. 42a, 13—20 (1987); received July 30 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0013.pdf
	Identifier	ZNA-1987-42a-0013
	Volume	42

4	Author	Isao Okada	Requires cookie*
	Title	MD-Simulation of Molten (Li, K)C1 at the Eutectic Composition. Self-Exchange Velocities of Li-and K-Isotopes near the Cl~-Ions
	Abstract	Molecular dynamics simulation (MD) has been done for a molten (Li, K)C1 mixture of the eutectic composition at about 700 K, 950 K and 1100 K and, for comparison, also for pure LiCl and KCl at about 950 K and 1100 K The atomic masses of half the Li + and K + ions have been set at 6.941 and 39.098, respectively. Self-exchange velocities (SEVs) of these cations have been calculated. The Chemla effect is reflected by the SEVs. The isotope effects of the SEVs in the mixture increase slightly with temperature. The motions of the cations with respect to the adjacent CI" are classified into four modes: (1) an oscillating motion, (2) a leaving motion, (3) a wandering motion and (4) a coming-back motion. It is found that the velocity of the leaving motion is dependent only on the masses and the temperature, and independent of the kind of cations and the composition.
	Reference	Z. Naturforsch. 42a, 21—28 (1987); received August 12 1986
	Published	1987
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	Identifier	ZNA-1987-42a-0021
	Volume	42

5	Author	K. Tanaka, N. Ogita, Y. Tamura, I. Okada, H. Ohtaki, G. Pálinkás, E. Spohr, K. Heinzinger	Requires cookie*
	Title	A Molecular Dynamics Study of the Structure of an LiCl * 3 H z O Solution
	Abstract	The structure of an 18.5 molal aqueous LiCl solution has been investigated by MD simulation. The total radial distribution function from the simulation agrees reasonably well with that of an X-ray diffraction measurement. In the average each Li + is in contact with one Cl~. Additionally, there are four water molecules in the first coordination sphere of Li + which occupy preferentially octahedral positions. The hydration shell of Cl~ is strongly disturbed by the formation of the contact ion pair. There is an almost complete breakdown of the water structure although the number of nearest neighbours is still four at the normal O-O distance in water. For the C1~-C1~ radial distribution a strong discrepancy exists between a neutron diffraction study with chloride isotope substitution and the simulation. All results are compared in detail with recently published data from a simulation of a 13.9 molal LiCl solution.
	Reference	Z. Naturforsch. 42a, 29—34 (1987); received August 1 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0029.pdf
	Identifier	ZNA-1987-42a-0029
	Volume	42

6	Author	R. Dabrowski, J. Baran, B. Sosnowska, J. Przedmojski	Requires cookie*
	Title	Binary Smectic Systems Including Trinuclear Pyrimidines with and without Nematic Gap
	Abstract	Phase diagrams of binary mixtures are presented in which one component has been selected from among four trinuclear isomeric pyrimidines forming a nematic or smectic A, phase, and the second one from cyanocompounds forming an A d smectic phase. Depending on the molecular structure of pyrimidine, mixtures were obtained that show or show not a nematic gap between the A, and A d smectic regions. In the latter case it was found that the relation = f(x) has two independent branches in different ranges of the concentration JC. The measured spacing of the smectic layers in such mixtures points to the possibility of the pyrimidine monolayer being transformed into a bilayer.
	Reference	Z. Naturforsch. 42a, 35—42 (1987); received May 28 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0035.pdf
	Identifier	ZNA-1987-42a-0035
	Volume	42

7	Author	T. G. Deligeorgiev, P. Nikolov, N. Tyutyulkov	Requires cookie*
	Title	Synthesis, Structure and Spectral Properties of Pyrylium Salts and Their Derivatives. I. 5,6-Dihydro-benzo(c)xanthylium Salts
	Abstract	The synthesis and spectral properties of a group of xanthylium salts are described. The longest wavelength absorption maximum in organic solvents (ethanol, 1,4-dioxane, acetonitrile) is the region 17 000-20 000 cm -1 , the molar absorptivity exceeding 30 000 1 • mol -1 cm -1 . The fluorescence Frank Condon transition is in the region 16 000-19 000 cm -1 , the fluorescence quantum yield of some of the compounds is greater than 0.9. The relation between the structure and the spectral properties of the molecules is interpreted by means of PPP-quantumchemical calculations.
	Reference	Z. Naturforsch. 42a, 43—48 (1987); received May 2 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0043.pdf
	Identifier	ZNA-1987-42a-0043
	Volume	42

8	Author	M. Stolze, D. H. Sutter	Requires cookie*
	Title	The Rotational Zeeman Effect of Pyrazole and Imidazole
	Abstract	The rotational Zeeman effect of the most abundant isotopic species of pyrazole and of imidazole has been studied under AM=Q and AM = ± 1 selection rules. With field close to 1.9 Tesla, the nuclear Zeeman effect uncouples the rotational angular momentum and the spins of the two nonequivalent l4 N quadrupole nuclei. The observed ^-tensor elements are g aa = -0.07498(14), g hh = -0.12531(13), and g cc = 0.06346(12) for pyrazole and g aa = -0.09339(16), g bb = — 0.10444(14), and = 0.06051(15) for imidazole. The values for the magnetic susceptibility anisotropies in units of 10" 6 erg/(G 2 mol) are 2Xaa ~ Xbb ~ Xcc = 39.53(24) and 2Xbb-Xcc'Xaa = 51.20(21) for pyrazole and 2* afl -Xbb -Xcc = 45.76(31) and 2Xbb -Xcc ~ Xaa = 42.19(41) for imidazole. (Given uncertainties are single standard deviations of the fit.) The so-called nonlocal (n-ring current) contributions to the out of plane components of the susceptibility tensor, / f n ° nlocal , derived as differences between the observed susceptibilities and values calculated from additivity rules for local atom susceptibilities, are compared to those derived earlier for other aromatic five membered ring molecules.
	Reference	Z. Naturforsch. 42a, 49—56 (1987); received August 30 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0049.pdf
	Identifier	ZNA-1987-42a-0049
	Volume	42

9	Author	Silvia Fleck, MichaelC. Böhm, Alarich Weiss	Requires cookie*
	Title	Dielectric and Pyroelectric Properties of Ammonium Hydrogen-DL-Malate Monohydrate, NH 4 (C 4 H 5 O S ) H 2 O
	Abstract	The dielectric and pyroelectric properties of ammonium hydrogen-DL-malate monohydrate NH® (e OOCCHOHCH 2 COOH) • H 2 0 were studied as a function of temperature and crystallo-graphic direction. The components of the dielectric tensor at room temperature are within the limits 5.9 S e ^ 8.6. The pyroelectric coefficient \p\ increases from « 18 (iC m~ 2 K _1 at T= 100 K to 32 (iC m" 2 K _1 at room temperature. The angular variation of p in the ac-plane of the crystal with symmetry Cc is ~ 10°. Using an INDO procedure which includes crystal field effects in a self-consistent way (SCEF) the charge distribution in the solid was calculated. With the therefrom resulting dipole moment and together with the dielectric measurements the pyroelectric coefficient j p \ and the change of \p \ with temperature was calculated. Experiment and theoretical result agree satisfactory.
	Reference	Z. Naturforsch. 42a, 57—66 (1987); received August 13 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0057.pdf
	Identifier	ZNA-1987-42a-0057
	Volume	42

10	Author	R. Büscher, G. Lehmann	Requires cookie*
	Title	Correlation of Zero-Field Splittings and Site Distortions. IX. Fe 3+ and Cr 3+ in /J-Ga 2 0 3
	Abstract	EPR of Fe 3+ in distorted tetrahedral sites in single crystals of /?-Ga 2 0 3 has been measured for the first time, and the second-order zero-field splitting (ZFS) parameters and principal axes directions were determined. The data for the sixfold coordinated Fe 3+ are in good agreement with results from the literature. Comparison of the ZFS patterns with those calculated from the crystal structure data using the superposition model (SPM) shows reasonable agreement in the orientations of the principal axes, but only for the tetrahedral site is a reasonable value of the intrinsic ZFS parameter obtained. Besides large uncertainties in the sizes of the distortions the crystal structure data also appear to be systematically wrong. For Cr 3+ in sixfold coordinated sites the discrepancies are even larger, but for this ion a reduced validity of the SPM may also be involved.
	Reference	Z. Naturforsch. 42a, 67—71 (1987); received August 12 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0067.pdf
	Identifier	ZNA-1987-42a-0067
	Volume	42

11	Author	Eckhard Fliege, Helmut Dreizler	Requires cookie*
	Title	Investigation of the Stark Shift of the Benzene-d, l 0 i — 0 00 Rotational Transition by Microwave Fourier Transform Spectroscopy
	Abstract	The Stark shift of the J' KL — J'^» 1 01 -OQO transition of benzene-di was investigated to determine the dipole moment caused by deuterium substitution. A modified set-up of the microwave Fourier transform spectrometer was used to be able to apply the necessary Stark voltage and to increase the sensitivity of the instrument. The resulting permanent dipole moment is n a = 0.00810(28) D corresponding to an absorption coefficient of y max = 2.8 • 10 -12 cm -1 , deter-mined at a sample pressure of 1.5 mTorr, for that line.
	Reference	Z. Naturforsch. 42a, 72—78 (1987); received September 9 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0072.pdf
	Identifier	ZNA-1987-42a-0072
	Volume	42

12	Author	W. Kasten, H. Dreizler	Requires cookie*
	Title	Nitrogen Quadrupole Coupling in the Microwave Spectra of Phenyl Isocyanate and Phenyl Isothiocyanate
	Abstract	The microwave spectra of phenyl isocyanate, C 6 H 5 NCO, and phenyl isothiocyanate, C 6 H 5 NCS, have been measured by microwave Fourier transform spectroscopy between 4.7 and 8.0 GHz and analysed for nuclear quadrupole hyperfine splitting due to l4 N.
	Reference	Z. Naturforsch. 42a, 79—82 (1987); received September 9 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0079.pdf
	Identifier	ZNA-1987-42a-0079
	Volume	42

13	Author	Nils Heineking, Helmut Dreizler	Requires cookie*
	Title	Nuclear Quadrupole Coupling Effects in the Rotational Spectrum of 4-Cyanopyridine
	Abstract	The quadrupole coupling of the two nitrogen nuclei was investigated by microwave Fourier transform spectroscopy. The results contribute to a comparison of substituent effects in different pyridine derivatives.
	Reference	Z. Naturforsch. 42a, 83—86 (1987); received August 23 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0083.pdf
	Identifier	ZNA-1987-42a-0083
	Volume	42

14	Author	Gerhard Taubmann	Requires cookie*
	Title	Diode Laser Spectroscopy of the v 3 Band of OF 2
	Abstract	Portions of the v 3 , asymmetric stretch band of OF 2 have been measured under conditions of Doppler-limited resolution and the frequencies of 176 transitions measured with a nominal accuracy of 0.001 cm -1 . The remaining band constants were determined by constraining the ground state parameters to the values determined earlier and earring out a simultaneous fit of the existing infrared and v 3 = 1 microwave data. No evidence for the anticipated effects of weak Coriolis coupling for levels with g 16 and 7^=30 was observed although such effects may present in levels with much higher quantum numbers.
	Reference	Z. Naturforsch. 42a, 87—90 (1987); received August 11 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0087.pdf
	Identifier	ZNA-1987-42a-0087
	Volume	42

15	Author	Ii Dibenzotetraphene, Pentaphenes, ZahidH. Khan	Requires cookie*
	Title	Electronic Spectra of Radical Cations and Their Correlation with Photoelectron Spectra
	Abstract	Absorption measurements on the radical cations of 3.4,8.9-dibenzotetraphene, pentaphene, 3.4-benzopentaphene, 6.7-benzopentaphene, and naphtho-(2'.3':6.7)pentaphene are made in the spectral region 7-50 kK. Electronic spectra of the cations are calculated using the Longuet-Higgins-Pople and Wasilewski type Open-Shell SCF-MO methods with limited configuration interaction. A detailed discussion of the absorption bands is given in the light of the calculations and the electronic transition energies of the cations derived from the ultraviolet photoelectron spectra of the parent hydrocarbons. The correlation between the optical and photoelectron spectra is closely examined and it is found to be excellent.
	Reference	Z. Naturforsch. 42a, 91—96 (1987); received September 5 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0091.pdf
	Identifier	ZNA-1987-42a-0091
	Volume	42

16	Author	H. Maes, G. Wlodarczak, D. Boucher, J. Demaison	Requires cookie*
	Title	The Millimeter-and Submillimeter-Wave Spectra of Acetaldehyde: Centrifugal Distortion and Internal Rotation Analysis
	Abstract	141 internal rotation doublets (282 transitions, among which 174 new measurements) of acetaldehyde in its ground torsional state have been measured up to 600 GHz (J S 32). An overall fit of the measurements (including the lines identified by previous workers) using the Internal Axis Method has allowed us to accurately determine the rotational, centrifugal distortion and internal rotation constants. The quality of the fit is good enough to permit the accurate prediction of transition frequencies of possible astrophysical interest.
	Reference	Z. Naturforsch. 42a, 97—102 (1987); received August 4 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0097.pdf
	Identifier	ZNA-1987-42a-0097
	Volume	42

17	Author	Jelena Radić-Perić, Miljenko Perić	Requires cookie*
	Title	Evaluation of Partition Functions of Triatomic Molecules Using Data Obtained by ab initio Calculations — Sums of States of Molecules with Spatially Degenerate Lowest Electronic States
	Abstract	The evaluation of partition functions of triatomic molecules based on data obtained by means of the ab initio method is discussed. Special attention is paid to molecules exhibiting the Renner-Teller effect. Various approximate approaches for the calculations of partition functions are ex-plicitly considered. The results are shown for HNF, NCO and BH 2 .
	Reference	Z. Naturforsch. 42a, 103—112 (1987); received July 14 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0103.pdf
	Identifier	ZNA-1987-42a-0103
	Volume	42

18	Author	J. Mayer, K. Urban, J. Härle, S. Steeb	Requires cookie*
	Title	Electron-Diffraction Study on an Amorphous Al-V Alloy Produced by Electron Irradiation of Quasicrystalline Al-16 at-%V
	Abstract	Quasicrystalline Al-16 at-%V was transformed to the amorphous state by low-temperature electron irradiation in a high-voltage electron microscope. Electron diffraction experiments were carried out in the amorphous state and in the crystalline state obtained after subsequent heat treatment. From the results the total structure factor was determined. The pair correlation function was calculated which yields the radii of the different coordination spheres and the total coordination number. The results are discussed in terms of current topological models of the structure of metallic glasses.
	Reference	Z. Naturforsch. 42a, 113—119 (1987); received October 4 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0113.pdf
	Identifier	ZNA-1987-42a-0113
	Volume	42

19	Author	M. M. Masoud, M. A. Bourham, W. Sharkawy, A. H. Saudy	Requires cookie*
	Title	Current Disruption Wave Generation
	Abstract	A fast energy wave packet pulse with a velocity greater than 10 8 cm/s has been generated from a T-shock tube, accompanying the discharge current disruption and a sharp voltage peak. The distribution of the disrupted wave increases the plasma temperature by 5 eV, and the density jumps to 2-3 times its initial value. The disruption wave streams through the proceeding plasma and shock wave without noticeable dissipative interaction. The production of a backward shock wave has been referred to the destruction of the wave at the expansion chamber. A propagated magnetosonic wave with a velocity of 6 x 10 5 cm/s has been detected, which was excited near the discharge electrodes.
	Reference	Z. Naturforsch. 42a, 120—122 (1987); received February 3 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0120.pdf
	Identifier	ZNA-1987-42a-0120
	Volume	42

20	Author	Jerzy Grzywacz, Zygmunt Trumpakaj	Requires cookie*
	Title	Influence of Inertial Effect on Fluorescence Anisotropy
	Abstract	The influence of inertial effects on the fluorescence anisotropy r is discussed. From recent work on the anisotropy of a prolate fluorescent molecule in a liquid solvent it is known that its estimated experimental moment of inertia is as much as about 3 orders of magni-tude greater than that calculated from its geometry. In this paper, by using a non-exponential form of the memory function K (t) in the generalized relaxation equation for /-(/), a satisfactory agreement between measured and calculated moments of inertia is obtained.
	Reference	Z. Naturforsch. 42a, 123—126 (1987); received May 16 1986
	Published	1987
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	TEI-XML for	default:Reihe_A/42/ZNA-1987-42a-0123.pdf
	Identifier	ZNA-1987-42a-0123
	Volume	42

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