bluuebunny/crossref_metadata_2025 huggingface dataset:
Molecular Dynamics and X-Ray Diffraction Study of Aqueous Beryllium(II) Chloride Solutions
Authors: Yamaguchi T. , Ohtaki H. , Spohr E. , Pálinkás G. , Heinzinger K. , Probst M. M.
Published: February 2015

A structural investigation of a 1.1 molal BeCl2 aqueous solution has been performed by a molecular dynamics simulation together with X-ray diffraction studies of 1.1 and 5.3 molal BeCl2 aqueous solutions at pH =1. A central force model in combination with an improved intramolecular three-body potential was used for water. The ion-water and ion-ion potentials were derived from ab initio calculations. The structure function obtained from the simulation is in satisfactory agreement with that from X-ray diffraction. The MD simulation of the 1.1 molal solution shows that the hydration shell o f Be2+ consists of six water molecules occupying octahedral sites around a central Be2+. The X-ray scattering data of the 5.3 molal solution indicate that Be2+ has only four water molecules in the first hydration shell. The average coordination number of Cl- is found to be about seven in the 1.1 molal solution from both X-ray diffraction and MD simulation, but Cl- is surrounded on the average by 3.4 water molecules in the 5.3 molal solution. The influence of the small divalent Be2+ on the geometry of its nearest neighbour water molecules is compared with the results of previous simulations of 1.1 molal MgCl2 and CaCl2 solutions.
On the Determination of Transition-Moment Directions from Emission Anisotropy Measurements
Authors: Kawski A. , Gryczyński Z.
Published: February 2015

Based on the theory of photoluminescence polarization, a description of the determination of transition-moment directions in luminescent molecules oriented in a stretched polymer film is given. This method is applied to the linear trans-diphenylpolyenes (C2h symmetry): 1,8-diphenyloctatetraene (DPO ), 1,6-diphenylhexatriene (DPH) and 1,4-diphenylbutadiene (DPB). The same transition moment polarized along the long axis o f DPO , DPH and DPB is responsible for absorption and fluorescence (β ≈ 0), when exciting in the long wave absorption band. The results are compared with relevant data obtained from dichroism measurements.
Ground- and Excited-State Absorption Spectra of 9-Acetoxy-10(4´-Acetoxy)phenylanthracenes
Authors: Heldt Janina R.
Published: February 2015

The ground-(S0) and excited -(S1 and T1) state spectra of seven derivatives o f 9-acetoxy- 10(4´-acetoxy)phenylanthracene were determined in the region 50000 - 15000 cm -1 (200 - 660 nm). Comparison of these spectra to the unsubstituted molecule (anthracene) indicates the presence o f bathochromic shift and the steric effect. The substituents cause changes of positions of the energy levels (bigger shifts are noticed for low lying states) and also changes of the absorption intensities of some transitions. The steric hindrances between the phenyl-substituents and the anthracene skeleton are more pronounced if the - OAc(- Me) group or a heavy atom is introduced at position 2´o f the phenyl ring. Molecules possessing such substituents at the meso-position exhibit spectroscopic properties characteristic for a plane molecule in the S0 and S1 states; they show a better preservation of the mirror symmetry between the absorption and fluorescence spectra, lower Stokes shifts and the destabilization energies and bigger fluorescence quantum yields.
Computer Averaging of Time-variable Signals by Autocorrelation
Authors: Roth Klaus
Published: February 2015

A general method is given for a computer accumulation of signals with unpredictable and variable drift with respect to the time-scale. By calculating the autocorrelation function of each individual scan via two forward Fourier transformations any time instability can be removed. Coaddition of the autocorrelation functions leads to the expected improvement in signal-to-noise ratio. Some examples for various signal shapes are given.
Nitrogen Quadrupole Coupling in the Microwave Ground State Spectra of Tertiary Butyl Isocyanide and Phenyl Isocyanide
Authors: Kasten W. , Dreizler H. , Andresen U.
Published: February 2015

The microwave ground state spectra of tert.-butyl isocyanide, (CH3)3CNC, and phenyl isocyanide, C6H5NC, have been measured by microwave Fourier transform spectroscopy in the region 5.0 to 8.0 GHz and analysed for nuclear quadrupole hyperfine splitting due to 14N. The nuclear quadrupole coupling constants are shown to be in accordance with structural predictions of the p-electron population at the nitrogen atom. The dipole moment of phenyl isocyanide was derived from the Stark effect of the JK-K+ = 202 - 101 transition.
On the Stability of Vitamin C Radicals
Authors: Eckert-Maksić M. , Bischof P. , Maksić Z. B.
Published: February 2015

Stability of vitamin C (ascorbic acid - AA) radicals is considered by the semiempirical MNDO method. It is found that AA⨪ is thermodynamically the most stable species. Interestingly, the AA⨪ radical is more stable than the parent AA. This finding is of great importance in view of omnipresence and versatility of the vitamin C in biochemical processes. The origin of the pronounced stability of AA⨪ is elucidated by a particular form of the energy partitioning technique.
Notizen: A Self Consistent Reaction Field Calculation of the Fluorobenzonitrile Radical Ions
Authors: Villar Hugo O. , Castro Eduardo A.
Published: February 2015

A self consistent reaction field study has been carried out at the MINDO/3 level, in order to explain the decomposition of the species in solution.
Binary Smectic Systems Including Trinuclear Pyrimidines with and without Nematic Gap
Authors: Dabrowski R. , Baran J. , Sosnowska B. , Przedmojski J.
Published: February 2015

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 Ad smectic phase. Depending on the molecular structure of pyrimidine, mixtures were obtained that show or show not a nematic gap between the A1 and Ad smectic regions. In the latter case it was found that the relation TSA → N= f(x) has two independent branches in different ranges of the concentration x. The measured spacing of the smectic layers in such mixtures points to the possibility of the pyrimidine monolayer being transformed into a bilayer.
Electronic Spectra of Radical Cations and Their Correlation with Photoelectron Spectra.
Authors: Khan Zahid H.
Published: February 2015

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 - 5 0 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.
Electron-Diffraction Study on an Amorphous Al-V Alloy Produced by Electron Irradiation of Quasicrystalline Al-16 at-%V
Authors: Mayer J. , Urban K. , Härle J. , Steeb S.
Published: February 2015

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.
Current Disruption Wave Generation
Authors: Masoud M. M. , Bourham M. A. , Sharkawy W. , Saudy A. H.
Published: February 2015

A fast energy wave packet pulse with a velocity greater than 108 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 105 cm/s has been detected, which was excited near the discharge electrodes.
Influence of Inertial Effect on Fluorescence Anisotropy
Authors: Grzywacz Jerzy , Trumpakaj Zygmunt
Published: February 2015

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 magnitude 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 r (t), a satisfactory agreement between measured and calculated moments of inertia is obtained.
Proton Spin Relaxation Study of Molecular Motions in the Lyotropic Liquid Crystalline System Potassium-Laurate Water
Authors: Kühner W. , Rommel E. , Noack F. , Meier P.
Published: February 2015

The paper presents and discusses measurements of the proton spin T1 relaxation dispersion over a broad frequency range (100 Hz - 300 MHz) in the micellar, hexagonal, cubic and lamellar phases of lyotropic potassium-laurate water mixtures. The results clearly show that in the anisotropic phases (hexagonal, lamellar) T1 at low Larmor frequencies is dominated by liquid crystalline order fluctuations, whereas this relaxation mechanism is negligible or absent in the isotropic phases (micellar, cubic). At medium and high Larmor frequencies the relaxation reflects rotational and translational molecular motions. Using theoretical models from the literature for the three kinds of reorientations the observed frequency and temperature dependences of T1 can be described quantitatively. In contrast to the order fluctuation mechanism the rotational and translational reorientations of individual molecules depend only weakly on the mesogenic structure. The order fluctuation contribution is strongest for the lamellar phase.
Top and Higgs Mass from Cancellation Conditions
Authors: Just K. , The L. S.
Published: February 2015

We propose a way of connecting the masses of all those particles which couple to the “electroweak” Higgs scalar. Up to radiative corrections to be given later, we expect mt = 81 GeV and mH = 66 GeV. Our realistic (but flexible) cutoff is explained as far as needed.
Notizen: Schwingungseigenschaften und thermodynamische Funktionen von Mn2O7
Authors: Baran Enrique J.
Published: February 2015

Vibrational Properties and Thermodynamic Functions of Mn2O7

The main force constants for Mn2O7 have been calculated from recently reported infrared data, using a simplified molecular model. Mean amplitudes of vibration and thermodynamic functions are also reported. The results are briefly discussed and some comparisons with related species are made.
Electron Density Distribution of a Single Hydrogen Perturbation in a Metal Lattice
Authors: Göbel K. , Wahl F.
Published: February 2015

The electronic structure of hydrogen centres stored in a metal crystal is described by a microscopic theory based on a functional energy difference method. That formalism works in a suitably chosen tensor product space built on a physical quasi-particle vacuum state. A transformation back to a bare Fock space representation is shown. This transformation operator divides the functional eigenvalue equation into a difference of two Schrödinger problems. The resulting state vectors can be used to calculate the electronic density distribution of a hydrogen excess electron in a metal lattice. The density function is obtained in a higher order approximation which considers the influence of three-particle correlations. A numerical solution is discussed for the case of a single hydrogen centre in a magnesium crystal. The plot shows that the excess electron is mainly localized in the surroundings of the corresponding hydrogen core. But with increasing host lattice extension there is more and more a non-vanishing probability to find the hydrogen electron dipped into the Fermi sea of metal electrons.
Bounds for the Hosoya Index
Authors: Gutman I. , Cioslowski J.
Published: February 2015

Some inequalities for Hosoya's topological index are deduced, revealing its dependence on the structure of the carbon-atom sekeleton of a hydrocarbon molecule.
Assignment for the Infrared Spectrum of Solid Sodium Propionate from Low-Temperature Measurements in Combination with 13C Isotopic Shifts
Authors: Kakihana Masato , Nagumo Tadashi
Published: February 2015

The infrared spectra of CH3CH2COONa and its 13C-labeled modifications (1-13C, 2-13C, and 3-13C) suspended in KBr disks were measured in the region 4000 -200 cm-1 at room temperature and liquid nitrogen temperature. Overlapping complex band contours appeared in some regions of the room temperature spectrum, most notably in the region 1500 -1350 cm-1, where 5 fundamentals having contributions from the methyl deformation, methylene bending, and carboxylate stretching modes should occur. In contrast to this, excellent resolution was reached at the low temperature, from which all 22 fundamentals expected in the whole spectral region investigated were detected. A complete assignment of the fundamentals is proposed mainly on the basis of the characteristic isotopic shifts of the three 13C substituted sodium propionate species. A fair number of the fundamentals were found to feature coupled modes having contributions from several group vibrations.
Hyperfine Structure in the Rotational Spectrum of Chloroacetonitrile
Authors: Merke Ilona , Dreizler Helmut
Published: February 2015

In continuation of previous studies on substituted acetonitriles, the chloroacetonitriles CH2
35ClCN and CH2
37ClCN are investigated. Substituted acetonitriles have earlier been studied in our laboratory [1]. The rotational spectra of the 35Cl- and 37Cl-species of chloroacetonitrile were investigated by Graybeal [2] and by Wada, Kikuchi, Matsumura, Hirota and Morino [3], with some controversy. The latter authors investigated also the deuterated species CD2
35ClCN and CD2
37ClCN. The main object of the present investigation was the analysis of the nitrogen hyperfine structure (hfs), which had not been analyzed before.
The Microwave Spectrum of 4-Methylisoxazole: 14N Nuclear Quadrupole Coupling, Methyl Internal Rotation and Electric Dipole Moment
Authors: Jäger W. , Dreizler H. , Mäder H. , Sheridan J. , Walls C. T.
Published: February 2015

The microwave spectrum of 4-methylisoxazole has been investigated in the frequency range from 8 to 40 GHz, employing both Stark and Fourier transform spectroscopy. We present the results from a 14N quadrupole hyperfine structure, a fourth-order centrifugal distortion and an IAM methyl internal rotation analysis. The components of the electric dipole moment with respect to the principal axes of inertia have been obtained from the Stark splittings of some rotational lines.
Geometry and Topology of SO(4) Trivializable Gauge Fields
Authors: Brucker R. , Sorg M.
Published: February 2015

The geometric and topological properties of SO(4)-trivializable SU(2) gauge fields are investigated in detail. The geometry of trivializable configurations is most adequately described by a conformally flat Riemannian structure, which yields a common geometric framework for both instantons and merons. In topologically nontrivial situations, the trivializable gauge fields exhibit a number of point defects (merons), which may be characterized by a quantized defect charge. The SO (2) reduction of the corresponding SU(2) bundle yields monopole configurations of the t'Hooft-Polyakov type.
The Structures of Two Hole Centers in the Mineral Brasilianite NaAl3(PO4)2(OH)4
Authors: Landrath K. D. , Lehmann G.
Published: February 2015

Two hole centers were detected in natural brazilianite by EPR at X-band and temperatures between 20 and 300 K. For the more intense center a hyperfine splitting (hfs) due to two nonequivalent Al nuclei could be completely analyzed by comparison of the hfs patterns with simulations for 1 ≦ A1/A2 ≦1.4. The orientation of the principle axes of these hfs tensors allowed to assign this hole to a specific oxygen in the lattice. The phosphorus bound to it is evidently exchanged against a lower valency cation, most likely Si4+ . In the second center a hfs splitting due to one Al and one P nucleus was identified. Although a complete analysis of their hfs tensors was not possible, this center could also be assigned to a particular oxygen for which evidently one adjacent Al is exchanged against a divalent ion.
Electron Energy Distribution Function (0 — 40 eV Range) in Helium in a Longitudinal Hollow-Cathode Discharge Used for Lasers
Authors: Mizeraczyk Jerzy
Published: February 2015

This paper presents results of measurements of the electron energy distribution function (EEDF) in the range 0 - 40 eV, and the electron density and the space potential for the helium plasma of a longitudinal discharge in a hollow cathode as used for He-inert gas and He-metal vapour lasers. The results show that the EEDF and also the mean electron energy, the electron density and the plasma potential differ from those typical of the transverse hollow-cathode discharge.
Extended Analysis of the K = 3 Inversion-Rotation Doublets for 14ND3 and ,15ND3 in the ν2 = 1 Excited State
Authors: Doose J. , Neustock W. , Guarnieri A.
Published: February 2015

Several K = 3 doublets of 14ND3 and 15ND3 in the ν2 = 1 excited vibrational state have been observed. With the new lines we were able to obtain improved values for the η3
0 and η3
J constants. For 14ND3 η3
0
= 2.3517(15) · 10-5 MHz, η3
J= -1.068(8) ·10-8 MHz, and for 15ND3 η3
0 = 2.3548(23) · 10-5 MHz, η3
J = 1.061(10)· 10-8 MHz.
The Calculation of 14N Quadrupole Coupling Constants with Basis Sets of High Local Quality
Authors: Gerber Stefan , Huber Hanspeter
Published: February 2015

An appropriate basis set to obtain electric field gradients close to the Hartree-Fock limit is evaluated for the nitrogen nucleus. An empirical correction for the error due to the neglect of electron correlation is given for sp-, sp2 - and sp3-hybrized nitrogen. The results are used to predict the full quadrupole coupling tensor for a few molecules. A breakdown of the electric field gradient into contributions from the single orbitals leads to a model for the field gradient due to the π-system and a partial rationalization of the part due to the σ-system. The results are discussed in relation to a Townes and Dailey analysis.
Notizen: Volume Changes on Melting for Several Rare Earth Chlorides
Authors: Igarashi K. , Mochinaga J.
Published: February 2015

Molar volumes in the liquid state and melting points of several rare earth chlorides RCl3 (R = La, Pr, Nd, Gd, Dy, and Y) have been measured by dilatometry and DTA. respectively. The volume changes on melting of these chlorides were evaluated on the basis of these result and available crystal structure data. The volume increase on melting of the hexagonal chlorides from LaCl3 to GdCl3 was found to be more than 20%. On the other hand, the volume changes of the monoclinic DyCl3 and YCl3 were less than 1%.
Notizen: Mittlere Schwingungsamplituden von Chromylbromid
Authors: González-Baró Ana C.
Published: February 2015

Mean amplitudes of vibration of CrO2Br2 in the temperature range between 0 and 1000 K have been calculated from recently reported spectroscopic data. The results are briefly discussed and compared with those of CrO2F2 and CrO2Cl2.
Invariant Relations for the Resistively Induced Plasma Flow Out of Tokamaks Under the Influence of Nonlinear Flow Terms and Ion Viscosity
Authors: Rebhan E.
Published: February 2015

The resistively induced plasma motion across the magnetic surface of a tokamak is considered taking into account nonlinear inertial flow terms and/or ion viscosity. It is shown that certain relations involving the plasma flow F out of the tokamak remain invariant if one goes from flows without these terms to flows including them. It is concluded that they can affect the flow F only indirectly by rearranging the plasma density, temperature and current distribution.
Quantum Mechanics and a Completely Integrable Dynamical System
Authors: Steeb W.-H. , Tonder A. J. van
Published: February 2015

From the eigenvalue equation (H0 + λV) \ ψn(λ)) = En (λ) | ψn( λ ) ) one can derive an autonomous system of first order differential equations for the eigenvalues En (λ) and the matrix elements Vmn(X) = ( ψm(λ) \ V \ ψn(λ), where λ is the independent variable. If the initial values En (λ = 0) and ψn (λ = 0) are known the differential equations can be solved. Thus one finds the “motion” of the energy levels En(λ). Here we give two applications of this technique. Furthermore we describe the connection with the stationary state perturbation theory. We also derive the equations of motion for the extended case H = H0 + λ\ Vt + λ2 V2. Finally we investigate the case where the Hamiltonian is given by a finite dimensional symmetric matrix and derive the energy dependent constants of motion. Several open questions are also discussed.
Photoacoustic Effect on Liquids Characterized by Transport Phenomena
Authors: Korpiun P. , Herrmann W. , Osiander R.
Published: February 2015

For a liquid sample the pressure variation in the gas is generated by a heat wave and an oscillating diffusive and convective flow of mass. It increases strongly with vapor pressure and, therefore, temperature, approaching a finite value the near boiling point. Experimental results confirm the model.
Internal Mobilities in the Molten Binary System (K,Rb)NO3
Authors: Yang Chao-cheng , Okada Isao
Published: February 2015

Ratios of internal cation mobilities in the molten binary system (K,Rb)NO3 have been measured with the Klemm method in a wide range of concentration (0.0537 < χRb< 1.00; χRb denotes mole fraction of RbNO3) and temperature (603 K < T < 783 K). From these and available data on the densities and conductivities, the internal mobilities of the two cations, bK and bRb, have been calculated. At high temperature and high ;cRb, the Chemla effect has been observed, whereas in previous similar experiments * the Chemla effect had not been observed. Except for xRb > 0.9, bK can be expressed by bK = [A /(V - V0)] exp (- E/RT), where V is the molar volume; A, E and V0 are constants having almost the same values as in the molten binary system (K,Cs)NO3.
23Na , 27Al, and 51V Multinuclear NMR-Imaging and NMR-Spectroscopy with a 1.5 T Imager
Authors: Braun M. , Lutz O. , Jung W. I. , Kischkel C. S. , Oeschey R. , Pfeffer M.
Published: February 2015

Nuclear magnetic resonance imaging has been perform ed with the nuclei 27A1, 51V, and 23Na in some test objects with a 1.5 T imager. Encouraging signal-to-noise ratios have been obtain ed within reasonable measuring times in the imaging and the spectroscopy mode using a commercially available 23Na headcoil.
Tokamak Transport Based on the Braginskii Model
Authors: Weitzner H. , Kerner W.
Published: February 2015

The two-fluid model of Braginskii is applied to the case of a moderately large tokamak. By estimation of the order of magnitude of the various effects and omission of small terms a somewhat simpler reduced two-fluid Braginskii model is obtained . The model applies on a time scale of order τemi/me , where τe is the electron-electron collision time, and energy confinement time is of this order. With electron and ion flow velocities no larger than is necessary to obtain the correct equilibrium currents, classical parallel viscosity becomes a dominant dissipative mechanism . The model allows for the slow evolution of equilibrium states. The equilibria, which include static, ideal magnetohydrodynamic equilibria as a special case, are described. Generally the number density, electrostatic potential, and flows are not constant on a flux surface. The procedure for determination of the slow time evolution of the equilibrium is sketched.
Criteria Governing Electron Plasma Waves in a Two-Temperature Plasma
Authors: Dell M. P. , Gledhill I. M. A. , Hellberg M. A.
Published: February 2015

Using a technique based on the saddle-points of the dielectric function, criteria are found which govern the behaviour of electron plasma waves in plasmas with two electron populations having different temperatures.
Electronic Structure of Al-Li Alloys by Means of Electron Microprobe
Authors: Franz W. , Lamparter P. , Steeb S.
Published: February 2015

By means of an electron microprobe the lithium-K-and aluminium-K-X-ray emission lines of Al-Li alloys were studied. The Li-line can be well described by the calculated emission line. The evaluation yields the transfer of electrons from the Li-s- to the Al-p-band during alloying. The charge transfer is enhanced by heat treatment. The dependence of the elastic modulus on the charge transfer is discussed.
Relation between the Emission Anisotropy and the Dichroic Ratio for Solute Alignment in Stretched Polymer Films
Authors: Gryczyński Z. , Kawski A.
Published: February 2015

For the determination of the angle β between the absorption and emission transition moments it seems appropriate to investigate the emission anisotropy as a function of the absorption dichroic ratio, Rd, rather than of the stretch ratio, Rs, of a polymer film. The angles ß thus determined for linear molecules of 1,8-diphenyloctatetraene (DPO), 1,6-diphenylhexatriene (DPH), 1,4-diphenylbutadiene (DPB), 4-dimethylamino-4'-nitrostilbene (DNS), and p-terphenyl (TP) are considerably smaller and closer to the zero value. Slight deviations of the angles obtained from β - 0° result from the effect of limited rotational motions of the luminescent molecules in the polymer.
1H and 19F NMR Studies on the Motion of Ammonium Ions in Solid Ammonium Tetrafluoroaluminate(III)
Authors: Hirokawa Kiyofumi , Furukawa Yoshihiro , Nakamura Daiyu
Published: February 2015

The temperature dependences of the NMR second moment, M2, and of the spin-lattice relaxation time, T1, of 1H and 19F nulcei were observed for NH4AIF4. With increasing temperature a decrease of M2(1H ), attributable to the onset of cationic reorientation, was observed between 77 and 150 K. This was confirmed by measurements of T1(1H) observed at two Larmor frequencies. Nonexponential magnetization recovery was detected in the T1 measurement of both 1H and 19F, especially below 150 K, indicating strong magnetic coupling between both systems. Therefore, in such cases T1 was determined from the initial slope of the magnetization recovery curve. The motional parameters of the cation were evaluated from the T1, data. The log T1 vs. T-1 curves of both nuclei showed a discontinuity around 143 K, indicating a phase transition which has already been suggested by other workers.
Molar Volumes of LaCl3-MCl (M = Li, Rb, and CS) Melts
Authors: Igarashi K. , Mochinaga J.
Published: February 2015

The molar volumes of LaCl3-MCl (M = Li, R, and Cs) melts were measured at 800 and 900 °C , and the molar volume isotherms at 900 °C are represented. They show positive deviations from additivity with the maximum at ca. 30mol% LaCl3. The excess molar volume was found to increase with increasing radius of the M+ cation.
Notizen: Dynamical Behavior During the Oxidation of Aniline with Bromate
Authors: Baier Gerold , Wegmann Klaus
Published: February 2015

Spontaneous oscillations occur during the oxidation of aniline with bromate in sulfuric acid (a Körös-Orban System). In a continuous flow, stirred tank reactor besides a simple relaxation oscillation of large amplitude, a small amplitude oscillation of higher frequency was observed, so were various dynamical phenomena which can be understood as a combination of the two simple oscillations. For some regions of parameter space, the appearance of deterministic chaos seems probable. The role of metal impurities is discussed.
The Evolution of Complex Systems
Authors: Hofacker G. L. , Levine R. D.
Published: February 2015

A principle of evolution of highly complex systems is proposed. It is based on extremal properties of the information I (X, Y) characterizing two states X and Y with respect to each other,

I(X, Y) = H(Y) -H(Y/X),

where H(Y) is the entropy of state Y,H (Y/X) the entropy in state Y given the probability distribu­tion P(X) and transition probabilities P(Y/X).

As I(X, Y) is maximal in P(Y) but minimal in P(Y/X), the extremal properties of I(X, Y) con­stitute a principle superior to the maximum entropy principle while containing the latter as a special case. The principle applies to complex systems evolving with time where fundamental equations are unknown or too difficult to solve. For the case of a system evolving from X to Y it is shown that the principle predicts a canonic distribution for a state Y with a fixed average energy .
1H NMR Studieson the Molecular Dynamics of Acetylferrocene in Crystals
Authors: Kubo Atsushi , Ikeda Ryuichi , Nakamura Daiyu
Published: February 2015

The temperature dependence of 1H spin-lattice relaxation time was determined at 20 MHz for solid acetylferrocene [(C5H5) (C5H4COCH3)Fe] from ca. 80 K up to the m.p. (359 K). Rather large activation energies of 21 and 24 kJ mol-1 for the C5 reorientations of the two crystallographically nonequivalent non-substituted cyclopentadienyl rings were obtained, indicating that the crystal has a closely packed structure. The two kinds of CH3 groups attached to the substituted cyclopenta­dienyl rings were assumed to be approximately equivalent and gave a low activation energy of 4 kJ mol-1 for the C3 reorientation. No phase transition was observed in the relaxation times or in additional experiments of differential thermal analysis although the presence of two phase transi­tions has been reported previously at temperatures immediately below the melting temperature by means of differential scanning calorimetry.
The Isotope Effect of Li-Ions in Countercurrent Electromigration of Molten LiOH
Authors: Yang Chao-cheng , Okada Isao , Nomura Masao , Okamoto Makoto
Published: February 2015

The relative difference, ε, in the internal mobilities of 6Li and 7Li ions in molten LiOH has been measured with the Klemm method. In the investigated range of temperature from 763 K to 873 K, ε has been determined to be 0.0068-0.0080 and seems to increase slightly with temperature.
Information Flow in 1D Maps
Authors: Kruscha K. J. G. , Pompe B.
Published: February 2015

An information theoretical description is given of the action of 1D maps on probability measures (e.g. on ergodic invariant measures of chaotic maps). On the basis of a detailed analysis of the elements of information flow the problem of optimum measuring of initial states for state predictions is discussed. Moreover, we give an information theoretical description of the relaxation, under the action of a map, of an initial probability distribution to any, not necessarily steady, final distribution. In this connection we formulate an H-theorem for 1D maps.
Delayed Choice with Correlated Photons
Authors: Rössler O. E.
Published: February 2015

A new experiment in the foundations of quantum mechanics is proposed. The existence of correlated photons -first seen by Wheeler -can be taken as a hint to devise a ‘‘double-wing’’ delayed choice experiment in Wheeler’s sense. A path choice (polarization choice) measurement made on the one side should then block an interference type measurement made on the other side (‘‘distant choice’’). A precondition for the combined measurement to work in theory is that the correlated photons used are of the ‘‘prepolarized’’ (Selleri) rather than the ‘‘unpolarized’’ (Böhm) type. A first EPR experiment involving prepolarized photons was recently performed by Alley and Shih. It may be used as a partial experiment within the proposed experiment.
The Microwave Spectrum of Cyanogen Iodide-15N: Hyperfine Structure and Electric Dipole Moment Investigated by Microwave Fourier Transform Spectroscopy
Authors: Gripp Joachim , Dreizler Helmut
Published: February 2015

The first rotational transition of cyanogen iodide-15N (IC15N) has been investigated by microwave Fourier transform (MWFT) Stark effect spectroscopy to determine the electric dipole moment. In addition the first four rotational transitions have been measured by MWFT spectroscopy to obtain accurate parameters for the rotational, quadrupole and spin-rotation coupling parameters.
The Effect of Intermolecular Interactions in Some Water Clusters and Hydrates of the Hydronium and Hydroxyl Ions, on their Polarisability and Hyperpolarisabilities. A Comparative Study
Authors: Waite J. , Papadopoulos M. G.
Published: February 2015

The polarisability and hyperpolarisabilities of (H2O)n, H3O+ (H2O)n and OH- (H2O)n are computed by the CHF-PT-EB-CNDO method. The basis set has been optimized with respect to the polarisability and second hyperpolarisability of H2O. The effect of intermolecular interactions, in the water clusters and the hydrates of the ions on their polarisability and hyperpolarisabilities, and their variation with charge, shape and size of the aggregates is discussed.
Kinetics and Mechanism of the 2+ 2 Cycloaddition of Tetracyanoethylene to 2,5-Dimethyl-2,4-Hexadiene
Authors: Asaad Adel N. , Aksnes Gunnar
Published: February 2015

The kinetics of the 2 + 2 cycloaddition reaction between tetracyanoethylene and 2,5-dimethyl- 2,4-hexadiene in different solvents has been studied by following the disappearance of the intermediate EDA-complex spectrophotometrically. It is concluded that the EDA-complex is transformed through a concerted cyclicpolar transition state to give the vinyl cyclobutane derivative (III). The effects of various solvents on the reaction rates have been analysed using a multiparameter approach. The thermodynamic parameters (ΔH0 and ΔS0), of EDA-complex formation and the activation parameters (ΔH# and ΔS#) of the cycloaddition have been discussed.
On the Structural Evolution of the Amorphous Al75Cu15V10 Alloy to the Icosahedral Phase
Authors: Matsubara E. , Waseda Y. , Tsai A. P. , Inoue A. , Masumoto T.
Published: February 2015

The transformations occurring on annealing an as-spun amorphous Al75Cu15V10 alloy are studied by X-ray diffraction and transmission electron microscopy (TEM). A continuous growth of icosahedral clusters, which are present already in the as-spun sample, is revealed. The size of the clusters estimated from the diffuse X-ray peak widths is consistent with the size of the modulation observed in the bright field TEM images.
Letter from Eötvös
Authors: Krause Wilfred
Published: February 2015

The original Eötvös data, which had resulted from a measurement series completed in 1908, and which recently found renewed interest, were not formally published until 1922. Now a resuming letter, written by Eötvös eighty years ago, has been re-discovered. The letter throwing some additio­nal light on his experiments is translated and briefly commented.
The Vibrational State Dependence of the 14N Quadrupole Coupling Tensor in Aniline . A Microwave Fourier-Transform Study Combined with Semirigid Bender Calculations
Authors: Kleibömer B. , Sutter D. H.
Published: February 2015

Experimental values for the diagonal elements of the 14N quadrupole coupling tensor derived from analysis of the hyperfine structure of low-J rotational transitions are reported for the two lowest states of the amino wagging mode. They show the expected difference due to averaging over the large amplitude amino wag.

A semirigid bender analysis of previously published infrared data provides the inversion angle expectation values for use in a quantum-chemical calculation of the corresponding effective Cou­lomb field gradients at the nitrogen nucleus.

The results are compared to those obtained earlier for the related molecules vinylamine, cyanamide and ammonia.
On Symbolic Dynamics of One-Humped Maps of the Interval
Authors: Grassberger Peter
Published: February 2015

We present an explicit construction of minimal deterministic automata which accept the languages of L-R symbolic sequences of unimodal maps resp. arbitrarily close approximations thereof. They are used to study a recently introduced complexity measure of this language which we conjecture to be a new invariant under diffeomorphisms. On each graph corresponding to such an automaton, the evolution is a topological Markov chain which does not seem to correspond to a partition of the interval into a countable number of intervals.
NM R Determination of the Fractal Geometry of Gels Around the Collapse Transition
Authors: Blinc R. , Jarh O. , Zidanšek A. , Blinc A.
Published: February 2015

The increase in the surface to volume ratio at the collapse transition of gels can be exploited to allow for an NMR determination of the fractal dimension of the gel surface in the liquid state where this quantity is hard to measure with other techniques. The measured quantities are the ratio be­tween the spin-lattice and spin-spin relaxation times T1/T2 of the liquid component and the ratio of the masses or volumes of the gel before and after the collapse transition. The technique has been used to determine the surface fractal dimen­sion of a blood plasma gel.
On the Phosphorescence of Benzologues of Furan , Thiophene , Selenophene , and Tellurophene . A Systematic Study of the Intra -annular Internal Heavy-atom Effect
Authors: Zander M. , Kirsch G.
Published: February 2015

Phosphorescence in ethanol and n-pentane at 77 K of the benzologues 1-8 of furan, thiophene, selenophene and tellurophene has been investigated. The rate constants of both the radiative (kPT) and non-radiative (kGT) deactivation of the lowest triplet state correlate linearly with

where ck denotes the Hückel AO coefficients in the HOMO of the carbon atoms bound to the hetero-atom and ζ is the spin-orbit coupling constant of the hetero-atom present. - The linear correlation observed between kPT and kGT is an example for the Orlandi-Siebrand rule. - The influence of an external heavy-atom perturber (methyl iodide) on phosphorescence lifetimes and the vibrational structure of phosphorescence spectra is the more efficient the less efficient is the internal perturbation caused by the intra-annular heavy-atom.
Normalization and Probability Densities for Wavefunctions of Quantum Fieldtheoretic Energy Equations
Authors: Stumpf H.
Published: February 2015

Quantum fields can be characterized by the set of transition amplitudes {〈0|π(A)|a〉V̶|a,〉∈V} where π(A) is a representation of the field operator algebra in V. This set has to satisfy renormalized energy equations and the elements of this set are called wavefunctions. However, these wavefunctions are not identical with wavefunctions of conventional quantum theory in Fockspace. Thus a theoret­ical interpretation is needed. In the present paper, by means of some theorems a method of normalization and construction of probability densities for these wavefunctions is given, which differs from the method of derivation of the normalization condition for Bethe-Salpeter amplitudes. The method can be applied both to nonrelativistic and relativistic fields with positive definite or indefinite state spaces, provided the renormalized energy equations possess finite solutions.
The Diode Laser Spectrum of Iodine Fluoride (IF)in the Ground Electronic State
Authors: Magg Ulrich , Birk Helmut , Nair K. P. R. , Jones Harold
Published: February 2015

The infrared absorption spectrum of the gas phase IF molecule in its ground state has been observed for the first time, using a diode laser spectrometer. The wavenumbers of transitions in the v = 1←0, and v = 2 ←1 bands have been measured with a nominal accuracy of +0.001 cm-1. These data were fitted along with the recently published microwave spectrum to produce an improved set Dunham T-parameters. Also the coefficients of the Dunham potential function for the electronic state of IF were determined by a direct fit to the experimental data.
Calculation of the Thermodynamic Solvent Isotope Effect for Ferrousand FerricIons in Water
Authors: Kneifel Charles L. , Friedman Harold L. , Newton Marshall D.
Published: February 2015

Molecular dynamics simulations of molecular models of Fe2+ and Fe3+ in water (L2O = H2O or D2O) are used to generate various correlation functions that characterize the respective hexaaquo hydration complexes. The static Fe2+-oxygen and Fe2+-hydrogen correlation functions are compared in detail with the first difference neutron diffraction results of Enderby et al. for Ni2+ . Velocity autocorrelation functions and corresponding power spectra are generated and analyzed for those modes of hydration shell water molecules whose reduced masses are most sensitive to the changes from H2O to D2O. Various approximations are applied to these data to calculate the solvent isotope effect on the difference in hydration free energies for Fe2+ and Fe3+ . These different approximations all lead to the qualitative conclusion that the net solvent isotope effect reflects a large degree of cancellation between the OL stretching modes and the librational modes. The simulation results generally agree with the results of earlier quantum chemical calculations applied to the same system, but in some respects the new results are not as realistic as the earlier ones. It is proposed that the agreement with experiment would be improved by changes in the model potential which are motivated by other, independent considerations.
High Resolution Spectrum of the CH3NCν2 Fundamental Band1
Authors: Markus M. W. , Yamada K. M. T. , Winnewisser G.
Published: February 2015

The spectrum of methyl isocyanide (CH3NC) has been measured in the region from 2148 cm-1 to 2179 cm-1 using a tunable diode laser spectrometer employing a newly designed signal averaging technique. The P-, Q-and R-branch lines of the ν2 fundamental band have been assigned for values of J ≤ 25, K ≤ 12. Molecular constants for the ν2 state have been determined including the quartic centrifugal distortion parameters.
Internal Cation Mobilities in the Molten Binary System(Na,NH4)NO3
Authors: Haibara Teruo , Odawara Osamu , Okada Isao
Published: February 2015

Relative differences in the internal cation mobilities in the molten binary system (Na, NH4)NO3 have been measured by Klemm's countercurrent electromigration method at NaNO3 mole fractions 0 0.3 and temperatures 433-453 K. Also the densities and electric conductivities of this system have been measured. From these data the internal cation mobilities, bNa and bNH₄, were calculated. Under all accessible conditions, bNH₄ is greater than bNa. The results are discussed in terms of the interaction between unlike ions and free space.
Derivation and Application of an Algorithm for the Numerical Calculation of the Local Orientation of Nematic Liquid Crystals
Authors: Kilian A. , Hess S.
Published: February 2015

Starting from a relaxation equation for the alignment tensor, an algorithm is derived which allows the numerical calculation of the dynamic and static behavior of the director field n with the correct nematic symmetry property, where n and - n are equivalent. As a first application, a two-dimensional problem is treated where the typical nematic defects with half-integer winding numbers only occur when the algorithm with the correct nematic symmetry property is used. Furthermore, the method is applied to the static and dynamic behavior of a Frederiks cell with strong and weak anchoring.
Rotational Diffusion and Rheological Properties of Liquid Crystals
Authors: Osipov M. A. , Terentjev E. M.
Published: February 2015

The rotational diffusion of a rod-like molecule in a liquid crystal is considered in the molecularfield approximation, and the corresponding Fokker-Planck equation is derived. It is shown that the microscopic friction coefficient, which is the parameter of this equation, possesses the usual exponential temperature dependence with the activation energy determined by the isotropic part of the intermolecular interaction energy. The viscous stress tensor of the nematic is obtained by averaging of the corresponding microscopic expression with the non-equilibrium distribution function. Finally, explicit expressions for the Leslie coefficients are obtained in terms of molecular parameters. Their values, signs and temperature variation correspond qualitatively to experimental data.
A Lorentz Invariant Schrödinger Equation for Spin 0
Authors: Trübenbacher E.
Published: February 2015

Using the concept of distributions, the square root of the operator - Δ + m2 is taken in a mathematically well defined way for one component wave functions. A new representation of proper Lorentz transformations for one component wave functions makes it possible to construct a relativistic quantum mechanics for spin 0, comprising a Lorentz invariant wave equation, a scalar product, and a positive definite density satisfying, together with a current, a continuity equation, and coupling of scalar and vector potentials.

Some interesting consequences of the theory concerning the concept of particle trajectory and velocity of propagation of the probability amplitude are discussed in detail. As an example of practical application a perturbation theory for discrete states is set up.
Effect of Isotopic Exchange upon Symmetry Dependent Fractionation in the O + CO → CO2 Reaction
Authors: Bhattacharya S. K. , Thiemens M. H.
Published: February 2015

In a recent study, it was demonstrated that the mechanism associated with the O + CO reaction produces a large, mass independent isotopic fractionation in the product CO2. A kinetic treatment of the data demonstrated that isotopic exchange between the O atom, produced by O2 photolysis and CO, occurred prior to the O + CO recombination. It was concluded that the likely source of the mass independent fractionation was the O + CO recombination. The present paper includes a kinetic evaluation of the added role of O + O2, along with O + CO, isotopic exchange. The new determinations provide a better fit of the experimental data.
Conductivity and Magnetic Properties of the Charge-Transfer Complex from N,N'-Dicyanonaphthoquinonedimimine (DCNNI)and Tetrathiafulvalene (TTF)
Authors: Werner H.-P. , Grauf W. , Schütz J. U. von , Wolf H. C. , Helberg H. W. , Kremer W. , Aumüller A. , Hünig S.
Published: February 2015

Conductivity (dc and ac), ESR-properties and proton relaxation rates of the charge transfer complex Tetrathiafulvalene N,N′-dicyanonaphthoquinonediimine in the temperature range be­ tween 300 K and 3.8 K are reported. This salt belongs to the unusual group of organic conductors, in which segregated donor and acceptor stacks are associated in a pairwise manner. The physical properties, which are compared with TTF-TCNQ, give evidence of non-stoichiometric charge transfer (ρ ≠ 1). A metal like state can be identified for T> 70 K, as is seen from the weak temper­ ature dependence of the conductivity (σrt ≈ 30 Scm-1) and the susceptibility (Xrt ≈ 7.5 ⋅ 10-4 emu/ mole) and from the Korringa like temperature dependence of the proton relaxation rates. The drop of the susceptibility at Tc ≈ 70 K and the activated temperature dependence of the conductivity for T < 70 K are explained by a metal-to-semiconductor transition.