bluuebunny/crossref_metadata_2025 huggingface dataset:
Chirale Dotierstoffe mit außergewöhnlich hohem Verdrillungsvermögen
Authors: Heppke G. , Lötzsch D. , Oestreicher F.
Published: February 2015

Mesogenic chiral esters of 1-phenyl-1,2-ethandiol, 1-cyclohexyl-1,2-ethanediol, 1,2-diphenyl- 1,2-ethanediol, 1,1´-bi-2-naphthol, 1-phenylethanol, 1-phenyl-2,2,2-trifluorethanol and 1-(9- anthryl)-2,2,2-trifluorethanol were synthesized. The temperature dependence of the molecular twisting power was determined in the nematic wide range mixture RO-TN 404. All compounds show good solubility and unusual high values of the molecular twisting power.
Dielectric and Pyroelectric Properties of Ammonium Hydrogen-DL-Malate Monohydrate, NH4(C4H5O5) H2O
Authors: Fleck Silvia , Böhm Michael C. , Weiss Alarich
Published: February 2015

The dielectric and pyroelectric properties of ammonium hydrogen-DL-malate monohydrate NH⊕ (⊖OOCCHOHCH2COOH) • H20 were studied as a function of temperature and crystallographic direction. The components of the dielectric tensor at room temperature are within the limits 5.9 ≦ ε≦ 8.6. The pyroelectric coefficient |p| increases from ≈ 18 μC m-2 K-1 at T= 100 K to 32 μC 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 |p| and the change of |p| with temperature was calculated. Experiment and theoretical result agree satisfactory.
Investigation of the Stark Shift of the Benzene-d1 101 — 000 Rotational Transition by Microwave Fourier Transform Spectroscopy
Authors: Fliege Eckhard , Dreizler Helmut
Published: February 2015

The Stark shift of the J'K′_K′+ - J″K_K″+ = 101 - 000 transition of benzene-d1 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 μa = 0.00810(28) D corresponding to an absorption coefficient of ymax = 2.8 • 10-12 cm-1 , determined at a sample pressure of 1.5 mTorr, for that line.
Nuclear Quadrupole Coupling Effects in the Rotational Spectrum of 4-Cyanopyridine
Authors: Heineking Nils , Dreizler Helmut
Published: February 2015

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.
Diode Laser Spectroscopy of the υ3 Band of OF2
Authors: Taubmann Gerhard
Published: February 2015

Portions of the υ3, asymmetric stretch band of OF2 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 υ3 = 1 microwave data. No evidence for the anticipated effects of weak Coriolis coupling for levels with K-1 ≦ 16 and J≦ 30 was observed although such effects may present in levels with much higher quantum numbers.
Microwave Spectrum and Nuclear Quadrupole Coupling of 2-Chloropyridine
Authors: Meyer M. , Andresen U. , Dreizler H.
Published: February 2015

The microwave spectrum of 2-chloropyridine, 2-Cl(C5H4N), has been studied to determine the 35Cl, 37Cl and 14N nuclear quadrupole coupling constants. The results are discussed within a simple MO theory. We propose an approximate r0-structure under certain assumptions. In addition to the ground state we observed one vibrationally excited state of both chlorine isotopic species of 2-chloropyridine.
Composite Gluons and Effective Nonabelian Gluon Dynamics in a Unified Spinor-Isospinor Preon Field Model
Authors: Stumpf H.
Published: February 2015

The model is defined by a selfregularizing nonlinear preon field equation and all observable (elementary and non-elementary) particles are assumed to be bound (quantum) states of the fermionic preon fields. In particular electroweak gauge bosons are two-particle composites, leptons and quarks are three-particle composites, and gluons are six-particle composites. Electroweak gauge bosons, leptons and quarks and their effective interactions etc. were studied in preceding papers. In this paper gluons and their effective dynamics are discussed. Due to the complications of a six-particle bound state dynamics the formation of gluons is performed in two steps: First the effective dynamics of three-particle composites (quarks) is derived, and secondly gluons are fusioned from two quarks respectively. The resulting effective gluon dynamics is a non-abelian SU(3) dynamics, i.e. this local gauge dynamics is produced by the properties of the composites and need not be introduced in the original preon field equation. Mathematically these results are achieved by the application of functional quantum theory to the model under consideration and subsequent evaluation of weak mapping procedures, both introduced in preceding papers.

PACS 11.10 Field theory.

PACS 12.10 Unified field theories and models.

PACS 12.35 Composite models of particles.
Infrared Spectrum of Pure Fluid Carbon Monoxide
Authors: Buback M. , Schweer J. , Tups H.
Published: February 2015

The infrared fundamental of pure CO is measured at supercritical temperatures between 298 K and 450 K up to a maximum pressure of 267 bar. The experimental IR bandshapes are adequately represented by summing up over the individual lines of the gaseous rotation-vibration spectrum assuming half-widths to be proportional to density. The molar integrated absorptivity is found to be independent of temperature and density which enables direct and precise measurements of CO concentrations in fluid phase equilibria and reactions.
A Deuteron NMR Study on a Benzene Multilayer on Graphite
Authors: Boddenberg B. , Grosse R.
Published: February 2015

An NMR sample tube was loaded with graphitized carbon black (Graphon) as well as a ten adsorbed layers equivalent of benzene-d6, and subsequently sealed. The 2H NMR spectra obtained at 298, 170 and 90 K yield the following picture: The multilayer phase with liquid like properties established at 298 K is decomposed at the lower temperatures into a bulk (3D) crystalline phase and an adsorbed phase of, probably, monolayer thickness which can be characterized to exist in the two dimensional (2D) fluid and solid states at 170 and 90 K, respectively.
Symmetry and Self-Similarity with Coupled Logistic Maps
Authors: Metzler W. , Beau W. , Frees W. , Ueberla A.
Published: February 2015

The symmetric coupling of two one-dimensional logistic maps displays different types of symmetric and asymmetric attractors on its route to chaos. Coexisting attractors possess basins in the phase space with Julia-like boundaries. Even classical fractal boundaries occur, when the basins of the coupled map with complex variables are explored. The self-similar features of the objects obtain particular fascination by their symmetries dependent on the map.
Self-Organized Formation of Spatial and Temporal Dissipative Structures in Semiconductors
Authors: Parisi Jürgen , Peinke Joachim , Röhricht Brigitte , Mayer Klaus Michael
Published: February 2015

Nonlinear current transport behavior during avalanche breakdown of germanium comprises the spontaneous symmetry-breaking evocation of both spatially inhomogeneous and temporally unstable dissipative structures in the formerly homogeneous semiconductor. Such kind of nonequilibrium order-disorder transitions are discussed in terms of two simple models based on the new circle-map formalism of universal scaling behavior and the well-known Rashevsky- Turing theory of morphogenesis.
A Microwave Fourier Transform Technique using Double Resonance Modulation
Authors: Stahl W. , Gripp J. , Heineking N. , Dreizler H.
Published: February 2015

We present a further modification of the double resonance technique in microwave FOURIER transform spectroscopy. The method is promising for the search of double resonances. It is demonstrated by three examples.
Dimerization of Carboxylic Acids in Solution up to High Pressures and Temperatures. 2. Benzoic Acid
Authors: Barraza R. , Borschel E. M. , Buback M.
Published: February 2015

Benzoic acid in dilute solution of n-heptane and of CCl4 is studied via high-pressure hightemperature IR spectroscopy on the C = O and O - H stretching fundamentals. Lambert-Beer’s law is shown to be valid for the C = O modes of the acid monomer and of the hydrogen-bonded cyclic dimer, which enables the quantitative measurement of the dimerization equilibrium to a maximum pressure of 2 kbar and up to 175 °C. At identical pressure and temperature the dimerization equilibrium constant is larger in n-heptane than in CCl4. From the monomer-cyclic dimer equilibrium constants the pressure dependence of the dimerization enthalpy is determined and compared with direct information on both species as derived from their O - H fundamental mode absorption. Toward lower temperature the dimerization volume is decreasingly negative and, in CCl4 solution, ΔV even changes sign around 40 °C. Increasing pressure thus favours the dissociation of the hydrogen-bonded dimer into benzoic acid monomer molecules at ambient temperature.
X-Ray Diffraction of Some Biphenylcyclohexanes (BCH's)
Authors: Ibrahim I. H.
Published: February 2015

X-ray diffraction measurements have been made on BCH5Cl, BCH5Br, BCH5CN, BCH52 and binary mixture of BCH5CN and BCH52, in the nematic phase. BCH5C1 and BCH5Br are thought to have a weak molecular correlation along the texture axis with repeat unit along that axis of ~ 1.1 molecular lengths. Whereas for BCH5CN the repeat unit along the texture axis is about 1.4 molecular lengths implying a strong molecular association.

The d-spacings of the binary mixtures of the strongly polar BCH5CN and the nonpolar BCH52, in the nematic phase, vary roughly linearly between the d-spacing of BCH5CN and that of BCH52.
Research on Nuclear Reactions in Exploding (Li + LiD) Wires
Authors: Lochte-Holtgreven Walter
Published: February 2015

It is shown that under certain conditions the nuclear reaction 7Li(d, n) 2α occurs within the plasma of "exploding" (Li + LiD)-wires. The reaction is not thermo-nuclear but of a hybrid character, i. e. the plasma is not heated to a sufficient temperature but electric fields complete the reaction. By an electrical discharge a (Li + LiD)-wire is heated to temperatures below 200 eV. After the heating the plasma expands turbulently. During this time, electrical fields postaccelerate the Li and D nuclei leading to the formation of the unstable 8Be followed by α-decay. These reactions occur frequently and are observed during a time much longer than one cycle. The energy of the α-particles does not remain in the plasma and can be used for external purposes. It is discussed why the exploding wire method has not led to results of practical interest in the past.
A Temperature Dependence Study of 35Cl Nuclear Quadrupole Resonance Frequencies in Some Hexachloroplatinate(IV) Hexahydrates
Authors: Sasane Akinobu , Shinohara Hisanori , Mori Yoshihiro , Kume Yoshio , Asaji Tetsuo , Nakamura Daiyu
Published: February 2015

The temperature dependence of 35Cl NQR frequencies was investigated in various hexachloroplatinate( IV) hexahydrates containing the following divalent ions as counter cations: Mn(II), Fe(II), Co(II), Ni(II), Cu(II), Zn(II), Cd(II), and Ba(II). All of the compounds except the Cu(II) and Ba(II) salts yield a single 35Cl NQR line at all temperatures studied. For the Mn(II), Cu(II), and Ba(II) salts, the NQR frequencies are considerably shifted by deuteration. For the deuterated Mn(II) salt, two 35Cl NQR lines were observed whose relative peak-height intensities vary in dependence on the history of the thermal treatment of the sample. The very broad higher frequency line could be observed for a sample which had been at 77 K or below. It could not be observed for a sample which was cooled slowly to room temperature after it had been heated up to ca. 420 K. A structural phase transition was located at 135.6 and 129.4 K for the Cu(II) salt and its deuterated analog, respectively. The frequency shift by deuteration is discussed in relation to the strength of O - H ... CI type hydrogen bonds.
Internal Cation Mobilities and Their Isotope Effects in the Molten System (Li, K)NO3
Authors: Lundén Arnold , Habasaki Junko , Okada Isao
Published: February 2015

With the Klemm method internal mobility ratios of the two cations have been measured for melts of the binary system (Li, K ) NO3 over a wide range of temperature and composition, and their isotope effects have been determined near the eutectic composition. The Chemla effect has been observed. With increasing temperature the Chemla crossing point shifts, as expected, toward higher concentrations of the smaller cation. At very high concentrations of LiNO3 the mobility of K+ tends to decrease, which is attributed to the free space effect. For both Li+ and K+ the isotope effect increases with temperature.
On the Phase Transition of Bis(pyridinium)hexachlorometallates, (C5H5NH)2[MCl6], M = Sn, Te, Pb, Pt. An X-Ray and 35Cl NQR Study
Authors: Borchers Dirk , Weiss Alarich
Published: February 2015

A phase transition has been observed in bis(pyridinium) hexachlorometallates (C5H5NH)2[MIVCl6]. M = Sn. Te. Pb. Pt. The crystal structure of the low temperature phase II of the salt with M = Sn was determined, space group C 1
ḷ- P 1̅, Z = 1 (a = 734.1pm, b = 799.0 pm, c = 799.7 pm,α= 83.229°. β = 65.377°, γ= 84.387°, T = 297 K). The four compounds are isotypic in phase II as well as in the high temperature phase I (C2H
2-B2 /m, Z = 2) for which the crystal structure is known for M = Te . The lattice constants of all compounds (both phases) are given. The temperature dependence of the 35Cl NQR spectrum was investigated. The three line 35Cl NQR spectrum is in agreement with the crystal structure. The dynamics of the pyridinium ring shows up in a fade out of part of the 35Cl NQR spectrum . The influence o f H ↔ D exchange on 35Cl NQR is studied and an assignment of ν (35Cl) ↔ Cl(i) is proposed. The nature of the phase transition P1̅ (Z = 1) ↔ B2 /m (Z = 2) is discussed.
Lattice Vibrations, MIR and FIR Optical Properties of Boron and Icosahedral Boron-Rich Borides I. Alpha-Rhombohedral Structure Group
Authors: Werheit H. , Haupt H .
Published: February 2015

General remarks on the structure and the lattice vibrations of the different structure groups o f boron and icosahedral boron-rich borides are made. In detail, the lattice vibrations of the alpha-rhombohedral boron structure group are systematically investigated by group theory. Reflectivity spectra of boron-carbide of different chemical com position and preparation and of B60 were measured in the MIR and FIR spectral range. These phonon spectra are analyzed in connection with previous experimental and theoretical results obtained by other authors. A proposal for the intercorrelation of the phonon spectra of this structure group is derived. The plasma resonance spectra of boron carbide and B6O yield qualitative information on the dependence of electronic transport on material properties.
Spin I = 1 NMR Patterns for the Case of Twofold Internal Spin Interactions
Authors: Boddenberg B. , Neue G.
Published: February 2015

An operator formalism is developed which allows a convenient calculation of high field spin I = 1 solid state NMR powder spectra for the case that the spins are acted on not only electrically via an electric field gradient tensor but also magnetically via a shielding tensor. Examples of practical applications in the field of surface science are given.
Oxidation of Malonic Acid by Ceric Ions Subset of the Belousov-Zhabotinsky Reaction
Authors: Försterling H.D. , Pachl R. , Schreiber H.
Published: February 2015

The kinetics of the Ce4+-decay and the formation of CO2 are measured in sulfuric acid solutions of malonic acid. The reaction rate is slowed down by Ce3+ -ions due to a reaction of Ce3+ with malonic acid radicals. The primary source of CO2 is the decarboxylation of malonic acid radicals. Implications on the mechanism of the BZ reaction are discussed.
EPR Characterisation of Bis(dimethylglyoximato)-Cobalt(II) Complexes and Their Oxygen Adducts Synthesised in an X-Zeolite Matrix
Authors: Lubitz W. , Winscom C. J. , Diegruber H. , Möseler R.
Published: February 2015

The synthesis of bis(dimethylglyoximato)-cobalt(II) (CoII(dmgH)2) in the α-cages of a cobalt-exchanged sodium X-zeolite is described. A simple hydration/oxygenation sequence culminating in a superoxo complex, CoIII(dmgH )2 · H2O · O2
- has been studied using X-band EPR spectroscopy. The identification of the precursor species: square-planar CoII(dmgH)2, distorted CoII(dmgH)2 and CoII(dmgH)2 · 2H2O was aided by comparison of their g- and 59Co hyperfine tensor principal values with those o f model complexes. On the basis of this identification the reaction sequence is discussed.
Luminescence Quenching of Rhodamines by Cyclooctatetraene
Authors: Targowski P. , Ziętek B. , Bączyński A.
Published: February 2015

Cyclooctatetraene (COT) as a quencher of fluorescence of a series of Rhodamine solutions was studied. The second order rate constants for the quenching process of Rhodamine 110, Rhodamine 19 pchl., Rhodamine 6G pchl., Rhodamine 6G, Tetramethylrhodamine, Rhodamine B and Rhodamine 3B pchl. are given. It was found that COT enhances rather intersystem crossing than internal conversion.
Self-Diffusion of Sodium, Chloride and Iodide Ions in Acetonitrile-Water Mixtures
Authors: Hawlicka E.
Published: February 2015

The self-diffusion coefficient of sodium, chloride and iodide ions in acetonitrile-water mixtures at 25.0 ± 0.05 °C has been measured in dependence on the salt molarity in the range 1.0 ·10-4 1.0 ·10-2 mol/dm3. The ionic self-diffusion coefficients in infinitely diluted solutions have been computed. The influence of the solvent composition on the solvation of the ions is discussed. Preferential solvation of the ions by acetonitrile above 15m ol% of acetonitrile has been found. An effect of the sodium ions on the formation of acetonitrile globules is postulated.
Variational Principle and Stability of Nonmonotonic Vlasov-Poisson Equilibria
Authors: Morrison P. J.
Published: February 2015

The stability of nonmonotonic equilibria of the Vlasov-Poisson equation is assessed by using nonlinear constants of motion . The constants of motion make up the free energy of the system , which upon variation yields nonmonotonic equilibria. Such equilibria have not previously been obtainable from a variation principle, but here this is accomplished by the inclusion of a passively advected tracer field. Definiteness of the second variation of the free energy gives a sufficient condition for stability in agreement with Gardner’s theorem [5], Previously, we have argued that indefiniteness implies either spectral in stability or negative energy modes, which are generically unstable when one adds dissipation or nonlinearity [6]. Such is the case for the nonmonotonic equilibria considered.
On the Reactions of Diphenyliodonium and Triphenylsulphonium Salts with Hydroxyl and 2-Hydroxy-2-Propyl Radicals
Authors: Yagci Yusuf , Pappas S. Peter , Schnabel Wolfram
Published: February 2015

Hydroxyl radicals react with diphenyliodonium ions, Ph2I+, and triphenylsulphonium ions, Ph3S+, in aqueous solution at room temperature with rate constants ≥ 5 x 109 l/mol s. These reactions lead to the formation of a broad transient absorption band with a maximum at ca. 370 nm, which is attributed to OH-adducts with cyclohexadienyl structures. 2-Hydroxy-2-propyl radicals react with diphenyliodonium ions in aqueous solution at room temperature with k2 = 6 x 107 l/mol s. The transient absorption band formed in this reaction has a maximum at about 390 nm and is attributed to diphenyliodo radicals, Ph2I·. In contrast, no detectable reaction occurred with 2-hydroxy-2-propylradical and triphenylsulphonium ion.
Lorentz Invariance as a Dynamic Symmetry
Authors: Winterberg F.
Published: February 2015

If all the forces of nature can be reduced to those which follow from a linear combination of a scalar and vector potential, as in electrodynamics, Lorentz invariance can be derived as a dynamic symmetry. All that has to be done is to assume that there is an all pervading substratum or ether, transmitting those forces through space, and that all physical bodies actually observed are held together by those forces. Under this assumption bodies in absolute motion through the substratum suffer a true contraction equal to the Lorentz contraction, and as a result of this contraction clocks in absolute motion go slower by the same amount. The velocity of light appears then to be equal in all inertial reference systems, if Einstein’s clock synchronization convention by reflected light signals is used and which presupposes this result. The Lorentz contraction and time dilation measured on an object at rest relative to an observer who gained a velocity by an accelerated motion is there explained as an illusion caused by a true Lorentz contraction and time dilation of the observer.

Both the special relativistic kinematic interpretation and this alternative dynamic interpretation give identical results only in the adiabatic limit where the accelerations are small, because if the Lorentz contraction is a real physical effect, it must take a finite time. However, to break the peculiar interaction symmetry with the ether, and which in the dynamic interpretation is the cause for the Lorentz invariance, the accelerated motions must involve rotation. Only then can non-adiabatic relativity-violating effects be observed and which would establish a preferred reference system at rest with the ether. Under most circumstances relativity-violating effects resulting from such a dynamic interpretation of special relativity would be very small and difficult to observe, a likely reason why they have evaded their detection in the past. For the rotating earth a residual sideral tide has been observed with a superconducting gravimeter, and which could be explained by an “ether wind” of about 300 km /sec at rest with the cosmic microwave background radiation. However, because of the observational uncertainties in measuring the terrestrial tides no definite conclusion can be drawn. A number of new experiments are therefore needed to decide the question regarding a possible weak violation of special relativity.
Smooth Decomposition of Generalized Fatou Set Explains Smooth Structure in Generalized Mandelbrot Set
Authors: Peinke J. , Parisi J. , Röhricht B. , Rössler O. E. , Metzler W.
Published: February 2015

Generalized Mandelbrot sets arise in perturbed (non-analytic) versions of the complex logistic map. Numerically, it contains smooth portions as shown previously. To exclude that this result is specific to particular initial conditions only, the structure of the analogue to the Fatou set is looked at in the region in question. The set of non-divergent points is being "eaten up" by a smooth invading boundary. Therefore, the same type of decomposition applies independent of position in parameter space, in the region in question.
Nitrogen Quadrupole Hyperfine Structure in the Rotational Spectrum of 2-,3-,and 4-Fluoro-Benzonitrile.A Comparative High Resolution Microwave Fourier Transform Study
Authors: Böttcher Olaf , Sutter Dieter H.
Published: February 2015

A microwave Fourier transform study of the rotational spectrum of 3-fluoro-benzonitrile was carried out to study the 14N quadrupole coupling and to give improved rotational constants and centrifugal distortion parameters. In order to fully exploit the high resolution inherent to the experimental technique, frequencies, linewidths, intensities and phases were directly fitted to the observed transient emission signals. The quadrupole coupling constants are discussed in comparison to those of the related molecules 2-fluoro-benzonitrile, 4-fluoro-benzonitrile, and benzonitrile itself. For this comparison a sufficient number of hfs-patterns of the latter molecules was remeasured to derive coupling constants of comparable reliability. The four molecules may be grouped into two pairs. In benzonitrile and in 3-fluoro-benzonitrile the CN-bond shows a smaller deviation from cylindrical symmetry than in 2-and 4-fluoro-benzonitrile.
Photoreactions of 2-Amino-2-Phenylindan-1,3-Dione Derivatives
Authors: Timtcheva I. , Nikolov P. , Zechner J. , Getoff N. , Minchev St.
Published: February 2015

The photochemical behaviour of several derivatives of 2-amino-2-phenylindan-1,3-dione, substituted in the amino group was investigated by means of steady state irradiation and flash photolysis. It is shown, that two photoisomerization reactions take place simultaneously: i) photoisomerization to 3-aminosubstituted-benzylidene-phthalides; ii) photoisomerization to 2-substituted-3-phenylisoquinolinones.Both processes result from a bond rupture according to a Norrish type I reaction mechanism.
The Soft Ion Model in Monte Carlo Simulation of Molten Salts
Authors: Margheritis C. , Sinistri C.
Published: February 2015

This paper describes a method for a simple evaluation of the polarization energy in molten salt systems, by which it is possible to go, without heavy computational cost, from the rigid to the soft ion model. The method is based on the observation that, within the movements of single ions in the Monte Carlo chain, the deviation of the polarization energy is a linear function of the deviation of the Coulomb energy.

An extended numerical application has been carried out for molten Lil at 800, 1200 and 1453 (b. p.) K. The parameters that are mostly affected by the used model are put into evidence.
Die Schwingungsfeinstruktur der Elektronenspektren des 13C- und 18O-markierten trans-Dioxotetracyanoosmats (VI),[OsO2(CN)4]2 -
Authors: Sartori C. , Preetz W.
Published: February 2015

The electronic absorption spectrum of the solid tetramethyl-ammonium salt of [OsO2(CN)4]2 - is measured at 10 K. The five distinct band systems exhibit vibrational progressions in the range 660-750 cm - 1, corresponding to the Os = O stretching vibrations sometimes coupled with ν(OsC). From this vibrational fine structure the electronic origin is deduced and verified by characteristic isotopic shifts by 18O and 13C. The two bands at lowest energy are assigned to the d-d-transitions 1A1g [b2
2g] → 3Eg [b1
2g e1
g] (620 - 460 nm) and 1A1g [b2
2g] → 1Eg [b1
2g e1
g] (490 - 400 nm). The 3Eg state is split by spin-orbit coupling into 5 components, from the one at lowest energy a luminescence emission (830 - 670 nm) takes place with a progression of 860 cm-1, corresponding to the symmetric Os = O stretching vibration in the electronic ground state. The more intense bands are assigned to charge transfer transitions from oxo π-orbitals into unoccupied niveaus of Os (VI): 1A1g [e4
u] → 3A2u [e3
u e1
g] (390 - 340); → 1A1u [e3
u e1
g] (340 - 290) and → 1Eu [e3
u b1
1g (290 - 230 nm). The singlet-triplet distances are 3200-3600 cm - 1. From a Franck-Condon analysis an excited state elongation of 10-13 pm for the osmyl groups is calculated.
Dielectric Relaxation of N-Methyl-2-Pyrrolidone in Polyvinylpyrrolidone
Authors: Dachwitz E.
Published: February 2015

Frequency dependent permittivity measurements on liquid mixtures of both substances in the relaxation region of N-methyl-2-pyrrolidone (MPy) show two spectral components originating from MPy. Pure MPy, on the other hand, exhibits only one component. The components are discussed as due to the microheterogenity of the mixtures.
Lie Series and Canonical Transformations in Complex Phase Space
Authors: Bruhn B.
Published: February 2015

This paper considers the Lie series representation of the canonical transformations in a complex phase space. A condition is given which selects the canonical mappings from the Lie transformations associated with a complex-valued generating function. Some special types of mappings and some simple algebraic tools are discussed.
Properties of Cold Condensed Metal Chlorideand of Cocondensed Metal/Metal Chloride Films II. Raman Spectra
Authors: Gottwald Helmut , Weil Konrad G.
Published: February 2015

We report on Raman spectroscopic investigations with cold condensed films of silver chloride, thallium chloride, and sodium chloride in the absence and in the presence of cocondensed metal. With films of 1000 nm -2000 nm thickness, Raman signals only can be seen if small silver particles are present. These are either cocondensed particles or they are formed by photolysis of silver chloride. At low temperatures, noncrystalline films can absorb light from the exciting laser, while at room temperature also crystalline silver chloride can be photolyzed by the argon ion laser.

The signals are interpreted as surface enhanced Raman transitions of a chloride - silver vibration. No indications for the presence of silver chloride or thallium chloride molecules can be found from the spectra.
Molecular Dynamics Study of a Lithium Ion in Ammonia
Authors: Hannongbua S. V. , Ishida T. , Spohr E. , Heinzinger K.
Published: February 2015

A Molecular Dynamics simulation of a solution of one Li+ in 215 NH3 molecules has been performed at an average temperature of 235 K. A newly developed flexible model for NH3 is employed and the Li +−NH3 interactions are derived from ab initio calculations. The structure of the solution is described by radial distribution functions and the orientation of the molecules. A solvation number of six is found for Li+ and a strong preference of the solvation shell molecules exists for an orientation where the Li + −N vector and the dipole moment direction of NH3 are parallel. The self-diffusion coefficient, the hindered translational motions and librations are calculated separately for the ammonia molecules in the solvation shell and in the bulk. The effect of Li + on intramolecular geometry and vibrations is reported.
Notizen: Oxidation of a Cyanine Dye with o-Cl-Dibenzoyle Peroxide and Peroxydisulphate
Authors: Habib A. M. , Abdel-Kader M. H. , Salem M. A. , Abdel-Halim S. T.
Published: February 2015

The oxidation of the cyanine dye 1-methyl-4-N-dimethylamine-γ-stilbazolium iodide with o-Cl dibenzoyl peroxide and peroxydisulphate ion is kinetically investigated. In both cases the oxidation process obeys second order kinetics, being first order in the oxidant molecule and first order in the cyanine dye. The thermodynamic parameters evaluated for the reaction between the dye and o-Cl-DBP are Ea = 45.6 kJ mol−1m, ΔH* = 43.09 kJ mol−1 and ΔS* = − 115.7 J deg −1 mol−1. The corresponding values of Ea, ΔH, and ΔS* obtained for the dye/S2O8
−2 system are 58.01 kJ mol−1, 55.5 kJ mol−1, and − 147.8J deg−1 mol−1. Proposed mechanisms are discussed.
Fractal Behaviour of Amorphous Ni32Pd52P16 Studied by SANS
Authors: Schaal M. , Lamparter P. , Steeb S.
Published: February 2015

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.
Application of Maximum Entropy Method (MEM) for Precise Determination of NQR Frequencies
Authors: Eguchi Taro , Mano Koichi , Nakamura Nobuo
Published: February 2015

The maximum entropy method (MEM) is applied to the analysis of the closely spaced nuclear quadrupole resonance spectra of 35Cl in hexachlorobenzene and 14N in trarts-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.
Absorption Spectrum of Mn2+ Ions Doped in Zinc Thallium Sulphate Hexahydrate
Authors: Rao J. Lakshmana , Reddy M. Ramachandra , Lakshman S. V. J.
Published: February 2015

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 transitions from the 6A1g(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 interaction. All the observed band positions have been fitted with the parameters B, C, Dq and α .
Phase Transition Studies across Isotropic-Smectic A and Smectic A-Smectic F Phases in 90.4
Authors: Potukuchi D. M. , Rao P. Bhaskara , Rao N. V. S. , Pisipati V.G. K. M.
Published: February 2015

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 isotropicsmectic 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 temperatures for IA transitions in other compounds are also presented.
The Dielectric Relaxation of Water on Addition of Ethylene Carbonate and some Related Substances
Authors: Stockhausen M. , Lux A.
Published: February 2015

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 assuming 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.
Structure Calculations on 1,3,4-Thiadiazole with Computer Programs
Authors: Stiefvater Otto L. , Rudolph H. D.
Published: February 2015

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.
A Study of Anonic Motions in Solid Rubidiumand Cesium Tetrachloroaurates(III)by Measuring the Temperature Dependence of Chlorine Nuclear Quadrupolar Relaxation Times
Authors: Ishikawa Atsushi , Asaji Tetsuo , Nakamura Daiyu , Ikeda Ryuichi
Published: February 2015

The temperature dependences of 35Cl NQR frequencies and 35Cl nuclear quadrupolar relaxation times T1Q and T2Q were determined above 82K for Rb[AuCl4] and CsfAuClJ up to ca. 340 and 320 K, respectively. Below these temperatures two 35Cl NQR frequencies were observed for each complex whereas no resonance could be detected above the respective temperatures. For both complexes, T1Q observed below ca. 270 K was interpreted as mainly determined by the rotary lattice vibration around the pseudo-C4(C4) axis and each Cl-Au-Cl diagonal axis of the square planar complex anion, whereas T1q observed above ca. 270 K was definitely shown to be determined through the reorientation of the anions about their C′4 axis. The activation energies for the C′4 reorientation of the anions was evaluated to be 71 and 53 kJ mol-1 for the rubidium and cesium salts, respectively. The anionic dynamics are discussed by assuming the motion of the anions within and out of the C4 potential wells at lower and higher temperatures, respectively.
The Lowest-Temperature Phase Transition of the Mixed Crystal of (NH4) 2(1−x)K2xPb[Cu(NO2)6] and the Reorientation of Ammonium Ions in the Crystals
Authors: Mizuno Motohiro , Asaji Tetsuo , Nakamura Daiyu
Published: February 2015

With decreasing temperature, the mixed crystal (NH4)2(1−x)K2xPb[Cu(NO2)6] at low potassium concentrations yields four solid phases, I, II, III, and IV. With increasing potassium concentration, the phase transition between III and IV disappears. By DTA, the corresponding transition temperature Tc was measured as a function of x. The mechanism of the phase transition is discussed, considering the reorientational motion of ammonium ions. The activation energy of (3 ± 1) kJ mol −1 for the motion of the ammonium ions obtained from our model agrees well with the experimental value of (2 ± 0.5) kJ mol−1 for the same motion in diamagnetic (NH4)2Cd2(NO2)6, which was studied as reference compound because its crystal structure is very similar. Tc of (NH4)2Pb[Cu(NO2)6] increased from 94 to 99 K by deuteration. This isotope effect is well interpreted in terms of the above model.
FT-IR Absorption Spectra of Polycrystalline Pressed Sample soft he Organic Metals and Superconductorsa α-β-(BEDT-TTF)2I3 and(BEDT-TTF)2Cu(NCS)2
Authors: Zamboni R. , Schweitzer D. , Keller H. J. , Taliani C.
Published: February 2015

IR absorption spectra of polycrystalline pressed samples of the organic metals α-(BEDT-TTF)2I3, β-BEDT-TTF)2I3 and (BEDT-TTF)2Cu(NCS)2 are presented and discussed. Normal protonated as well as deuterated materials were studied. The spectra range from 400 cm-1 to 5000 cm-1 and are similar to the IR reflectance spectra reported ealier. The data are of special interest in view of the fact that recently bulk superconductivity was observed in such polycrystalline samples of organic metals, and therefore the application of organic superconductors for the preparation of electronic devices seems possible.
Semiclassical and Quantum Mechanical Calculations of Isotopic Kinetic Branching Ratios for the Reactionof O(3P) with HD
Authors: Lynch Gillian C. , Halvick Philippe , Truhlar Donald G. , Garrett Bruce C. , Schwenke David W. , Kouri Donald J.
Published: February 2015

Tunneling probabilities for the reactions O + HD → OH + D and O + DH → OD + H have been calculated by semiclassical dynamical methods and compared to accurate quantal calculations for the same potential energy surface. The results are used to test the reliability of variational transition state theory with the least-action semiclassical method for tunneling probabilities for the prediction of intramolecular kinetic isotope effects.
New Evidence for Symmetry Dependent Isotope Effects: O+CO Reaction
Authors: Bhattacharya S. K. , Thiemens M. H.
Published: February 2015

The isotopic fractionation associated with the O + CO reaction has been studied using oxygen atoms produced by room temperature O2 photolysis at two different wavelengths, 185 and 130 nm. A large mass-independent isotopic fractionation is observed in the product CO2, extending the range of this type of reaction beyond O + O2 and SF5 + SF5.

Kinetic evaluation of the data restricts the source of the mass-independent fractionation mechanism to the O + CO recombination step rather than O2 photolysis, secondary ozone formation, or O2 photodissociation. At least one, and most likely two other fractionation processes appear to occur in the experiments, and interpretation of the isotopic results is tentative at present. Based on the relevant reaction rates and the value for the reduced partition function for isotopic exchange between O and CO, it is suggested that this process may occur prior to the δ17O≅δ18O recombination process. Secondary CO2 photolysis may superimpose an additional fractionation. The experimental data are also examined in the context of a model based upon energy randomization rates versus the lifetime of the activated complex.
Quasi-Chemical Model for Liquid Li-Cd Alloys
Authors: Prasad L. C. , Singh R. N.
Published: February 2015

The quasi-chemical model based on pairwise interactions is used to study the concentration dependent thermodynamic properties of Li-Cd liquid alloys. Special attention is given to the concentration-concentration correlation function in the long wavelength limit [Scc(0)] and the chemical short-range order parameter (CSRO). The activity, free energy of mixing, Scc(0) and CSRO are computed as functions of temperature and concentration.
Application of a PC-Controlled MW-Spectrometer for the Analysis of Ketene-D2. Simultaneous Analysis of Vibrational Excited States Using Microwave and Infrared Spectra
Authors: Doose J. , Guarnieri A. , Neustock W. , Schwarz R. , Winther F. , Hegelund F.
Published: February 2015

D2CCO has been investigated in the first excited vibrational states of the ν9, ν6, and ν5 vibrations. About 150 transitions have been measured partly at room temperature and partly at 360 K using a micro- and millimeter-wave spectrometer provided with an averaging system using a personal computer. Rotational and centrifugal distortion constants have been obtained for the excited states mentioned. A simultaneous least squares analysis of these MW-data with upper state combination differences obtained from FT-IR data has been carried out. Improved sets of molecular parameters have been obtained.
Deuterium Nuclear Quadrupole Coupling in Deutero-Isocyanic Acid
Authors: Heineking N. , Gerry M.C. L. , Dreizler H.
Published: February 2015

The deuterium quadrupole hyperfine structure has been resolved in the 6(1, 5)-6(1, 6) transition of deutero-isocyanic acid (DNCO), and has been used to evaluate the previously undetermined coupling constant (Χbb - Χcc)- With the assumption of cylindrical symmetry for the deuterium quadrupole coupling tensor its principal values have been estimated and have been found to be in excellent agreement with a theoretical prediction. Within experimental error the z-principal quadrupole axis and the D -N internuclear axis coincide.
Proton Spin Relaxation in Reentrant Nematic Cyano -biphenyl Liquid Crystals
Authors: Schweikert K. H. , Noack F.
Published: February 2015

The frequency dependence of the longitudinal proton spin relaxation time T1 was measured by field-cycling and standard NMR techniques in the nematic, smectic and reentrant nematic mesophases of the reentrant liquid crystal 6OCB-8OCB. The results clearly demonstrate that, in contrast to conclusions reported in the literature, the underlying relaxation mechanisms are the same for the nematic and reentrant nematic order, but different in the nematic and smectic phase. In particular, at low frequencies the nematic and reentrant samples reveal a square-root dispersion profile (T1,~ ν½) characteristic for nematic director fluctuations, whereas the smectic samples show a dissimilar and only very narrow dispersion step. It can be attributed to a linear relaxation time increase (T1 ~ v1) expected for smectic-type order fluctuations. The experimental data are described and discussed in terms of four molecular processes, namely nematic or smectic order fluctuations, self-diffusion, rotational motions, and a resonant proton nitrogen coupling.
Ferroelektrische Flüssigkristall - Mischungen mit Kohlenhydrat - Derivaten als Dotierstoffe / Ferroelectric Liquid Crystal Mixtures with Carbohydrate Derivates as Dopants
Authors: Vill V. , Fischer F. , Thiem J.
Published: February 2015

For the first time carbohydrate derivatives were studied as dopants for calamitic smectic phases. Fast switching ferroelectric cells could be realized, and electroclinic effects were observed. By inversion of configuration at a chiral center of these compounds switching times, solubility, and helical twisting power vary by orders of magnitude. The studied derivatives showed modest solubility properties.
Hydrogen in Electrodynamics. IV. The Components of the Hydrogen Field
Authors: Sallhofer Hans
Published: February 2015

After a discussion of the one-component Schrödinger (1926) and the four-component Dirac (1928) representation of hydrogen it is shown that the six-component electrodynamic picture turns out to be considerably simpler and clearer. The computational effort is reduced to a fraction.
Self-Diffusion and Reorientation of Methylammonium Ions in (CH3NH3)2ZnCl4 Crystals as Studied by 1H-NMR
Authors: Ishida Hiroyuki , Iwachido Tadashi , Hayama Naomi , Ikeda Ryuichi , Terashima Mifune , Nakamura Daiyu
Published: February 2015

Differential thermal analysis, differential scanning calorimetry, and measurements of the 1H spin-lattice relaxation times and second moments of 1H-NMR absorptions were performed on methylammonium tetrachlorozincate (II) crystals over a wide temperature range. A solid-solid phase transition was located at 477 K. From the 1H-NMR experiments it was found that the cations undergo overall reorientation as well as three dimensional translational self-diffusion in the high-temperature phase. In the low-temperature phase, a 120° reorientational motion of the CH3 and NH3
+ groups of the cation about its C-N bond axis was detected. The parameters for the motional modes of the cations in the crystal were evaluated from the analysis of the 1H-NMR experimental results.
Pars Orbital Method for Excited States
Authors: Polansky Oskar E. , Fabian Walter M. F.
Published: February 2015

Based on a projection operator formalism the pars orbital method is reformulated for the general case that both the molecule M as well as the reference molecule L-are described by a CI-expansion of the wave function. Some numerical examples in which the method is used for the interpretation of the ultraviolet spectra of simple organic molecules (butadiene, aniline, benzonitrile, o-, m-, and p-aminobenzonitrile, 2,5-diamino-p-benzoquinone) in terms of the various states (ground as well as excited) of the respective reference molecules are discussed in some detail to illustrate the scope and limitations of the proposed formalism. The results of these calculations are in addition compared to results obtained by two other methods (configuration analysis and specific measures of partial distances) designed to allow an analysis of molecules in terms of the constituent fragments.
Labile Trace Elements in Some Antarctic Carbonaceous Chondrites: Antarctic and Non-Antarctic Meteorite Comparisons
Authors: Paul Rick L. , Lipschutz Michael E.
Published: February 2015

We report data for Ag, Au, Bi, Cd, Co, Cs, Ga, In, Rb, Sb, Se, Te, TI, U and Zn determined by radiochemical neutron activation analysis in consortium samples of Belgica (B) 7904, Yamato (Y) 82042, Yamato 82162 and Yamato 86720 carbonaceous chondrites. These trace elements cover a wide volatility/mobility range and give unique information on thermal histories of meteorites. The results indicate the unique nature of these carbonaceous chondrites. Y-82042 proves to have the volatile element pattern of a C2 ( ≡CM) chondrite and the petrologic characteristics of a CI (n≡CI) chondrite. These must be primary nebular condensation/accretion features, unaffected by post-accretionary processes. The other three meteorites were thermally metamorphosed in ≧2 parent regions over the 600-700 °C range, at relative temperatures B-7904 < Y-82162< Y-86720. Before heating, B-7904 and Y-86720 had C2-levels of volatile elements: Y-82162 had uniquely high volatile element concentrations, at about CI-levels. The data require a new classification scheme for such chondrites. Belgica 7904 and Y-82162 and -86720 seem to be derived from one or more thermally altered carbonaceous asteroids, and their spectral characteristics should be compared with those of B-, F-, G- or T-asteroids. These results indicate substantial differences in the thermal histories of Antarctic and non-Antarctic CI and C2 chondrite populations. In reviewing all that is known about the Antarctic and non-Antarctic meteorite populations, the overwhelming weight of evidence supports the view that these populations sample different extraterrestrial source materials, differing in thermal histories. It may be that over the extended collecting period of the Antarctic ice sheet, it has sampled a considerably greater proportion of near-Earth asteroids than do current falls.