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1	Author	W. Schuster, Stiller	Requires cookie*
	Title	R
	Abstract	The locked-dipole model for reactions between ions and polar molecules is modified by introduc ing the moment of inertia into the centrifugal term of the interaction potential. The resulting rate coefficients are compared with other models and experimental data. Key words: Gases -ions -momentum of inertia -polar molecules -reaction kinetics M o m e n t o f I n e r tia In flu e n c e o n I o n -M o le c u le R e a c tio n R a te s
	Reference	Z. Naturforsch. 44a, 1—3 (1989); received September 12 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0001.pdf
	Identifier	ZNA-1989-44a-0001
	Volume	44

2	Author	P. Schaal, S. Lamparter, Steeb	Requires cookie*
	Title	M
	Abstract	Small angle neutron scattering (SANS) was done with meltspun amorphous Ni32Pd52P16 in the as-quenched state as well as after annealing at 533 K, 570 K. and 607 K, 20 h each. The double logarithmic plot of the structure factor versus the momentum transfer shows linear behaviour with noninteger Porod-slopes. The results are interpreted with the scattering from fractally rough inner surfaces. The as-quenched state contains fluctuations of the scattering length density associated with smooth boundary interfaces. Annealing yields rough boundary interfaces, the roughness being largest after the 570 K annealing. Annealing at the higher temperature of 607 K yields less rough boundary interfaces. F r a c t a l B e h a v io u r o f A m o rp h o u s N i3 2P d 52P 16 S tu d ie d b y S A N S
	Reference	Z. Naturforsch. 44a, 4—6 (1989); received September 23 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0004.pdf
	Identifier	ZNA-1989-44a-0004
	Volume	44

3	Author	P. Kizler, P. Lamparter, S. Steeb	Requires cookie*
	Title
	Abstract	It is shown that it is possible to set up a structural model for the amorphous Fe90Zr10-aIloy which is in agreement both with diffraction and XANES data, the latter being sensitive to higher than binary correlations. A M o d e llin g a n d X A N E S S tu d y o n th e S tr u c tu r e o f th e A m o rp h o u s F e 90Z r 10-A llo y
	Reference	Z. Naturforsch. 44a, 7—14 (1989); received October 17 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0007.pdf
	Identifier	ZNA-1989-44a-0007
	Volume	44

4	Author	Taro Eguchi, Koichi Mano, Nobuo Nakamura	Requires cookie*
	Title	A
	Abstract	p p lic a tio n o f M a x im u m E n tro p y M e th o d (M E M) f o r P r e c is e D e te r m in a tio n o f N Q R F re q u e n c ie s The maximum entropy method (MEM) is applied to the analysis of the closely spaced nuclear quadrupole resonance spectra of 35C1 in hexachlorobenzene and 14N in frarts-azobenzene. The superiority of the MEM to usual FFT spectra is discussed with respect to the precision of frequency measurements and the noise characteristics in broad and noisy NQR spectra.
	Reference	Z. Naturforsch. 44a, 15—18 (1989); received November 3 1988
	Published	1989
	Keywords	Maximum Entropy Method, Nuclear Quadrupole Resonance, Phase Transition, Spec tral Analysis
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0015.pdf
	Identifier	ZNA-1989-44a-0015
	Volume	44

5	Author	J.Lakshmana Rao, M.Ramachandra Reddy, S.V J Lakshman	Requires cookie*
	Title	A
	Abstract	b s o rp tio n S p e c tru m o f M n 2+ I o n s D o p e d in Z in c T h a lliu m S u lp h a te H e x a h y d r a te The optical absorption spectrum of Mn2+ ions doped in zinc thallium sulphate hexahydrate has been studied at room and liquid nitrogen temperatures. The observed bands are assigned as transi tions from the 6Alg(S) ground state to various excited quartet levels of Mn2+ ion in octahedral symmetry. The fine structure observed in the 4T2g(D) band is explained as due to spin-orbit interac tion. All the observed band positions have been fitted with the parameters B, C, Dq and y..
	Reference	Z. Naturforsch. 44a, 19—22 (1989); received November 10 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0019.pdf
	Identifier	ZNA-1989-44a-0019
	Volume	44

6	Author	D. M. Potukuchi, P.Bhaskara Rao, N.V S Rao, V.G K M Pisipati	Requires cookie*
	Title	P h a s
	Abstract	e T ra n s itio n S tu d ie s a c ro s s I s o tr o p ic -S m e c tic A a n d S m e c tic A -S m e c tic F P h a s e s in 9 0 .4 The temperature dependence of the density of N(p-n-nonyloxy benzylidene)p-n-butylaniline (90.4) is studied. The compound exhibits smectic A, smectic F and smetic G phases. The isotropic-smectic A (IA) and smetic A-smectic F phase transitions are found to be first order. The calculated thermal expansion coefficient and differential scanning calorimetry support the density results. The density jumps, associated enthalpies and the estimated pressure dependence of the transition tem peratures for IA transitions in other compounds are also presented.
	Reference	Z. Naturforsch. 44a, 23—25 (1989); received August 12 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0023.pdf
	Identifier	ZNA-1989-44a-0023
	Volume	44

7	Author	G. Chiodelli, V. Campari-Viganò, G. Massarotti, Flor	Requires cookie*
	Title	G
	Abstract	The electrical behaviour of La2_JtSrJ.Cu04_v solid solutions (with x = 0, x = 0.025, x = 0.05, and x = 0.15) at temperatures between 10 and 900 K and under different oxygen partial pressure pQl — 1 -M0~6 atm) has been investigated. The samples prepared and measured under an 0 2 flux (i.e~, with y = 0) show a superconducting transition with Tc = 46, 29. 37 K for x = 0. 0.05 and"0.15, respectively. The samples with x = 0.025, y = 0, and x = 0, y = t= 0 exhibit no sign of superconductivity. In the temperature range 100-900 K. La2Cu04 is semiconducting, whereas the electrical resistivity is independent of temperature for the x =0.025 sample, and the x = 0.05 and x = 0.15 are metallic.
	Reference	Z. Naturforsch. 44a, 26—28 (1989); received September 19 1988
	Published	1989
	Keywords	Superconductors, electrical properties, defects
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0026.pdf
	Identifier	ZNA-1989-44a-0026
	Volume	44

8	Author	OttoL. Stiefvater	Requires cookie*
	Title
	Abstract	e d S u b s titu tio n S tr u c tu r e o f l,3 ? 4 -T h ia d ia z o le by D R M M ic ro w a v e S p e c tr o s c o p y Double Resonance Modulation (DRM) microwave spectroscopy has allowed the determination of the complete substitution structure of normal, mono-deuterated and perdeuterated 1,3.4-thiadiazole (N,C2H2S). The shift of the centre of gravity between the normal and the d2-form and the swing of inertia! axes relative to the C2v symmetrical forms in the 2-d,-species have been used to revise the small coordinates of hydrogen and deuterium atoms. Bond lengths (in Ä) and bond angles (in degrees), with uncertainties covering all three molecular forms, are found as follows: S -C =1.7200 [3] < CSC = 86.38 [2] C -N =1.3031 [5] * SCN =114.64 [3] N -N =1.3711 [5] * CNN = 112.17 [1] C-H /D = 1.0771 [4] * SCH/D = 122.49 [2] The results suggest that the shift and the swing of inertial axes between different 'parent' forms, which can both be determined from the moments of multiply substituted molecular isotopes, may be used with advantage to refine the position of near-axis atoms.
	Reference	Z. Naturforsch. 44a, 29—40 (1989); received September 27 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0029.pdf
	Identifier	ZNA-1989-44a-0029
	Volume	44

9	Author	Jutta Hartmann, Shi-Qi Dou, Alarich Weiss	Requires cookie*
	Title	C
	Abstract	r y s ta l S tr u c tu r e o f P ip e ra z in iu m D ib ro m id e M o n o h y d r a te a n d P ip e ra z in iu m M o n o io d id e The l'Br and 12 I NQR spectra were investigated for 1,2-diammoniumethane dibromide, -diiodide, 1,3-diammoniumpropane dibromide, -diiodide, piperazinium dibromide monohydrate, and pipera zinium monoiodide in the temperature range 77 ^ T/K ^ 420. Phase transitions could be observed for the three iodides. The temperatures for the phase transitions are: 400 K and 404 K for 1,2-di-ammoniumethane diiodide, 366 K for 1,3-diammoniumpropane diiodide, and 196 K for piperazinium monoiodide. The crystal structures were determined for the piperazinium compounds. Piperazinium dibro mide monohydrate crystallizes monoclinic, space group C2/c, with a= 1148.7 pm, 0 = 590.5 pm, c= 1501.6pm, /?= 118.18°, and Z = 4. For piperazinium monoiodide the orthorhombic space group Pmn 2l was found with a = 958.1 pm, b = 776.9 pm, c = 989.3 pm, Z = 4. Hydrogen bonds N — H ... X with X = Br, I were compared with literature data. 79B r, 127I N Q R o f D ia m m o n iu m a lk y l H a lid e s a n d P ip e ra z in iu m H a lid e s .
	Reference	Z. Naturforsch. 44a, 41—55 (1989); received October 22 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0041.pdf
	Identifier	ZNA-1989-44a-0041
	Volume	44

10	Author	M. Stockhausen, A. Lux	Requires cookie*
	Title	T
	Abstract	h e D ie le c tric R e la x a tio n o f W a te r on A d d itio n o f E th y le n e C a r b o n a te a n d so m e R e la te d S u b s ta n c e s The dynamic dielectric properties of diluted aqueous solutions of propylene carbonate, ethylene carbonate (EC). 4-butyrolactone and cyclohexanone (CH) have been measured at 20 C. On as suming normal solute relaxation, the water relaxation can be described by two superimposed Debye type contributions, which may be interpreted in terms of a hydration model. Qualitatively, the influence on the water relaxation increases from EC to CH.
	Reference	Z. Naturforsch. 44a, 56—58 (1989); received November 25 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0056.pdf
	Identifier	ZNA-1989-44a-0056
	Volume	44

11	Author	D. Siebert, J. Dahlem, S. Fiechter, A. Hartmann	Requires cookie*
	Title
	Abstract	Synthetic pyrite crystals doped with halogen (CI, Br) or manganese (Mn) were investigated by ESR at 78 K with an X-band spectrometer and a TE102 cavity with lOOkc field modulation. The crystals were preferably measured with the directions <100>, <110), and <111) parallel to the static magnetic field H0. The ESR spectrum of Mn-doped crystals showed a sextet which can be explained by a spin-Hamiltonian for an electron spin S = 1/2 in interaction with the nuclear spin / = 5/2 of the Mn nucleus for axial symmetry. Due to the observed spin and due to the orientation of the paramagnetic centers the spectra were assigned to Mn2+ in the low spin state which resides on cation site in the FeS-, lattice. In halogen-doped crystals four pairs of lines can be interpreted by the interaction of the two isotopes of / = 3/2, 79Br, 81 Br and 35C1, 37C1, respectively, with an electron spin S — 1/2. According to the observed symmetry of the ESR signals the paramagnetic centers can be explained as (S-X)2~ radicals (X = CI, Br) which substitute for the (S2)2~ dumb-bells of pyrite. All crystals evoked extremely narrow ESR lines, especially the halogen-doped crystals with linewidths down to 0.03 mT. Excellent agreement between measured and calculated spectra up to the finest details has been obtained. A n E S R In v e s tig a tio n o f S y n th e tic P y r ite C r y s ta ls
	Reference	Z. Naturforsch. 44a, 59—66 (1989); received November 12 1988
	Published	1989
	Keywords	Pyrite, ESR anorganic radicals, hyperfine coupling, spin densities
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0059.pdf
	Identifier	ZNA-1989-44a-0059
	Volume	44

12	Author	Detlef Stryjewski, Nils Heineking, Helmut Dreizler	Requires cookie*
	Title	N
	Abstract	itro g e n H y p e r fin e S t r u c t u r e in th e R o ta tio n a l S p e c tr a o f 4 -P y r id in e c a r b a ld e h y d e a n d 3 -P y rid in e c a rb a ld e h y d e We have resolved and analysed the nuclear quadrupole hyperfine structure in the rotational spectra of 4-pyridinecarbaldehyde and 3-pyridinecarbaldehyde, C5H4NCHO. The results are dis cussed and compared to those of previously measured pyridine compounds. The electron withdraw ing effect of the aldehyde-function, in the 3-and 4-position at the ring system, has been calculated, and the differences in the results are discussed.
	Reference	Z. Naturforsch. 44a, 67—70 (1989)
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0067.pdf
	Identifier	ZNA-1989-44a-0067
	Volume	44

13	Author	H-N, Hiroyuki Ishida, Tadashi Iwachido, Naomi Hayama, Ryuichi Ikeda, Miyuki Hashimoto, Daiyu Nakamura	Requires cookie*
	Title	S
	Abstract	tr u c tu r a l P h a s e T ra n s itio n s in S o lid te r t-B u ty la m m o n iu m N i t r a t e a s S tu d ie d by D iffe re n tia l T h e r m a l A n a ly s is a n d ' Seven solid phases including three metastable phases of (CHjJjCNHjNC^ were revealed by differential thermal analysis in the temperature range between 80 K and the melting point (418 K), and cationic dynamics in each phase was studied by use of 'H-NMR techniques. The highest-temperature solid phase obtainable above 412 K was found to be an ionic plastic phase, where the cations perform rapid translational self-diffusion and overall rotation about their center of gravity.
	Reference	Z. Naturforsch. 44a, 71—74 (1989); received November 3. 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0071.pdf
	Identifier	ZNA-1989-44a-0071
	Volume	44

14	Author	G. H., A. Redhardt, H.-J Steinhoff, J. Schütter, H.-J Neumann, G. Hess	Requires cookie*
	Title	H
	Abstract	ig h e r O r d e r M o d e s a s A c c u ra c y L im itin g F a c to r in P e r m ittiv ity M e a s u r e m e n ts o f H ig h L o s s y F lu id s U s in g T ra n s m is s io n T e c h n iq u e s in th e The higher order mode distortion in measuring dielectric constants on high lossy, high permit tivity liquids in the GHz range is investigated by a simulation procedure as well as by experiment. For this, a homodyne method for measuring e* is introduced in analogy to precision EPR-work.
	Reference	Z. Naturforsch. 44a, 75—80 (1989); received October 12 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0075.pdf
	Identifier	ZNA-1989-44a-0075
	Volume	44

15	Author	K. Kynev, V. Kuk	Requires cookie*
	Title
	Abstract	It is shown that a ZnS:Eu phosphor with line emission spectrum can be prepared without coactivator introduction, contrary to previous results. The broad-band emission established in ZnS: Eu, Li is ascribed to the formation of Eu2 + centres due to the removal of lattice stress by lithium incorporation.
	Reference	Z. Naturforsch. 44a, 81—83 (1989); received September 27 1988
	Published	1989
	Keywords	Zinc sulphide, luminescence spectrum, europium line emission, phosphor preparation
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0081.pdf
	Identifier	ZNA-1989-44a-0081
	Volume	44

16	Author	Kirsten Vormann, Helmut Dreizler	Requires cookie*
	Title	1
	Abstract	^ -Q u a d r u p o l e H y p e rfin e S tr u c tu r e in th e R o ta tio n a l S p e c tru m o f P h e n y ld iflu o ro b o ra n e We present an investigation and interpretation of the 11 B-quadrupole hyperfine structure (hfs) in the rotational spectrum of phenyldifluoroborane in the torsional ground state of the BF2 group. The measurements were made with a microwave Fourier transform (MWFT) spectrometer in the fre quency range between 5 and 8 GHz. Experimental and Analysis
	Reference	Z. Naturforsch. 44a, 84—86 (1989); received December 10 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0084.pdf
	Identifier	ZNA-1989-44a-0084
	Volume	44

17	Author	Z. Naturforsch	Requires cookie*
	Title	T
	Abstract	h e r m io n ic E le c tro n E m issio n o f T u n g s te n B ro n z e s. K 0 3 0 W O 3 a n d R b 0 30W O 3 F. The work functions and thermionic constants of the hex agonal tungsten bronzes K0 30WO3 (— 1.76 eV, A = 3 A/ cm2 K2) and Rb0 30WO3 (<p = 1.88 eV, A = 10 A/cm2 K2) are determined and compared with those of the corresponding alkaline metals and hexagonal Cs0 305WO3.
	Reference	Z. Naturforsch. 44a, 87 (1989); received November 2 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0087_n.pdf
	Identifier	ZNA-1989-44a-0087_n
	Volume	44

18	Author	O. Böttcher, N. Heineking, M. Andolfatto, D. H. Sutter	Requires cookie*
	Title	M
	Abstract	o le c u la r ^r1-v a lu e , M a g n e tic S u s c e p tib ility A n is o tro p y , a n d D e u te riu m Q u a d r u p o le C o u p lin g C o n s ta n t in D e u te ro d ia c e ty le n e To Professor Helmut Dreizler, Pioneer of NWFT-spectroscopy, on the Occassion of his 60th Birthday The rotational Zeeman effect in the J'-* J = 2 -1 rotational transition and the deuterium quadru pole coupling effect in the J'-J = 1-»0 transition have been observed for D — C = C — C = C — H using a microwave Fourier transform (MWFT)-spectrometer. The molecular parameters determined are: rotational constant B0= 4084.452 MHz, deuterium quadrupole coupling constant e q Q (D) = 217(6) kHz, molecular g^-value = 0.0073(1) and molecular magnetic susceptibility anisotropy {% L — X\\) — 11-5(7) 10-6 erg Cj 2mol_1.
	Reference	Z. Naturforsch. 44a, 89—94 (1989); received December 12 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0089.pdf
	Identifier	ZNA-1989-44a-0089
	Volume	44

19	Author	OttoL. Stiefvater, Adran Cemeg, Coleg Prifysgol, Gogledd Cymru, BangorLl57 2uw, U.K H D Wales, Rudolph	Requires cookie*
	Title	S
	Abstract	tr u c tu r e C a lc u la tio n s on 1 ,3 ,4 -T h ia d ia z o le w ith C o m p u te r P r o g r a m s Dedicated to Professor Helmut Dreizler on the Occasion of His 60 th Birthday Insertion of the 14 available sets of isotopic moments of 1,3,4-thiadiazole into the computer programs GEOM or RU 111/115 confirms the previously hand-calculated structure parameters of this molecule, but does not further improve the accuracy of those results.
	Reference	Z. Naturforsch. 44a, 95—98 (1989); received December 19 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0095.pdf
	Identifier	ZNA-1989-44a-0095
	Volume	44

20	Author	R. Schwarz, G. Gliemann	Requires cookie*
	Title	P
	Abstract	o la riz e d O p tic a l A b s o rp tio n a n d E m is s io n o f P t (I I) C o m p le x e s : S in g le C r y s ta l \|P t(o -p h e n) (e n) ] C l2 • 2 H 20 The influence of temperature (1.9^ T^ 295 K) on the polarized optical absorption and emission spectra of single crystal [Pt(o-phen)(en)]Cl2 • 2 H20 is reported. Analysis of the spectra shows that the emission at low temperatures originates from the states of three types of traps located energeti cally by Av<5 cm-1, 43 cm-1, and 194 cm-1, respectively, below the triplet exciton band.
	Reference	Z. Naturforsch. 44a, 99—105 (1989); received November 23 1988
	Published	1989
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	TEI-XML for	default:Reihe_A/44/ZNA-1989-44a-0099.pdf
	Identifier	ZNA-1989-44a-0099
	Volume	44

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