bluuebunny/crossref_metadata_2025 huggingface dataset:
Large-Angle X-ray Scattering Investigation of the Structure of 2-Propanol–Water Mixtures
Authors: Takamuku Toshiyuki , Saisho Kensuke , Aoki Sachiko , Yamaguchi Toshio
Published: February 2015

The structure of 2-propanol and its aqueous mixtures has been investigated at 25°C, using a large-angle X-ray scattering (LAXS) technique. The total radial distribution function of neat 2-propanol has shown that hydrogen-bonded chains of 2-propanol molecules are formed. In the 2-propanol-water mixtures, 2-propanol chains predominate at mole fractions x2pr > ~ 0.1. When x2pr decreases from x2pr = 1, the number of hydrogen bonds reaches a plateau of 3.4± 0.1 at x2pr ≤ ~0.1, suggesting that the tetrahedral-like structure of water is mainly formed. On the basis of the present findings, together with previous results on methanol-water and ethanol-water mixtures, effects of hydrophobic groups on the structure of the alcohol-water mixtures are discussed. The heat of mixing at 25°C as a function of x2pr has been interpreted in terms of the structural transition of solvent clusters.
Charge Transfer and Transport in Polymer-Fullerene Solar Cells
Authors: Parisi J. , Dyakonov V. , Pientka M. , Riedel I. , Deibel C. , Brabec C. J. , Sariciftci N. S. , Hummelen J. C.
Published: February 2015

The development of polymer-fullerene plastic solar cells has made significant progress in recent years. These devices excel by an efficient charge generation process as a consequence of a photoinduced charge transfer between the photo-excited conjugated polymer donor and acceptor-type fullerene molecules. Due to the paramagnetic nature of the radical species, the photo-induced charge transfer can be analyzed by the help of light-induced electron spin resonance spectroscopy. Upon looking at an interpenetrating donor-acceptor composite consisting of the polymer MDMOPPV and the fullerene derivative PCBM, we disclose two well separated line groups having a strongly anisotropic structure. The line shape can be attributed to an environmental axial symmetry of the polymer cation and a lower rhombohedric symmetry of the fullerene anion. Since the signals were found to be independent of one another with different spin-lattice relaxation times, the radical species can be discriminated via separate characterization procedures. In order to study the bulk charge transport properties, we carried out admittance spectroscopy on the polymer-fullerene solar cell device including a transparent semiconductor oxide front contact (ITO/PEDOT:PSS) and a metal back contact (Al). The temperature- and frequency-dependent device capacitance clearly uncovers two different defect states, the first, having an activation energy of 9 meV, indicates a shallow trap due to a bulk impurity, the latter, having an activation energy of 177 meV, can be assigned to an interfacial defect state located between the polymer-fullerene composite and the metal back contac
Mössbauer Investigation of γ-Fe2O3 Nanocrystals in Silica Matrix Prepared by the Sol-gel Method
Authors: Cannas C. , Concas G. , Congiu F. , Musinu A. , Piccaluga G. , Spano G.
Published: February 2015

A series of Fe2O3-SiO2 nanocomposites (25 weight % of Fe2O3) has been prepared using a sol-gel method. Samples showing different features were obtained by varying the evaporation conditions acting on the surface / volume ratio of the starting sol. The samples were investigated using Mössbauer spectroscopy at low temperature. The Fe2O3 nanoparticles have been identified as maghemite ( γ-Fe2O3) particles. The samples show a superparamagnetic behavior with a blocking temperature that depends on the average particle size.
The Instability of a Viscoelastic Conducting Cylindrical Interface Supporting Free-surface Currents
Authors: El-Dib Yusry O. , Moatimid Galal M.
Published: February 2015

The stability of a viscoelastic interface acted upon by an oscillating azimuthal magnetic field is studied. The interface separates two rigid magnetic fluid columns. Only azimuthal disturbrance modes are considered in a linear perturbation technique. Weak viscoelastic effects are taken into consideration, so that their contributions are demonstrated in the boundary conditions. The presence or absence of free surface currents resulted in a dispersion equation with complex coefficients of the Mathieu type. It is found that the surface currents disappear when the stratified magnetic field becomes unity. The phenomenon of coupled resonance is observed. Several special cases are reported. A set of graphs are drawn to illustrate the influence of the various parameters on the stability of the considered system.
Odd-even Effect in a Homologous Series of 4-n-Alkylbenzoic Acids: Role of Anisotropic Pair Potential
Authors: Ojha Durga Prasad , Kumar Devesh , Pisipati V. G. K. M.
Published: February 2015

CNDO/2

A computational analysis based on quantum mechanics has been carried out to determine the association energy of seven homologues of the 4-n-alkylbenzoic acid series (n = 3, 4, 5, 6, 7, 8, and 9), using the Rayleigh-Schrödinger perturbation method for various nearest neighbour configurations of interacting pairs. The net atomic charges and dipoles have been computed using the method. An attempt is made to explain the odd-even effects at the molecular level on the basis of these results.
A Novel Antiferroelectric Liquid Crystal with two Asymmetric Centres
Authors: Kumar P. A. , Pisipati V. G. K. M.
Published: February 2015

An antiferroelectric liquid crystal material, (S)-4-(2-chloro-3-phenyl-1-(2-methylbutyloxy)carbomato- 4ʹ-n-dodecyloxy biphenylcarboxylate (CPCDBD), has been synthesized by using (S)-2-amino- 3-(4-hydroxy)phenyl propionic acid (L-tyrosine) as one the optically active ingredients. Preliminary investigations on this material reveal high spontaneous polarization (~ 145 nC/cm2) in the antiferroelectric Sm-CA
* phase. Possible structural contributions towards the appearance of antiferroelectric ordering are discussed.
Planck Mass Rotons as Cold Dark Matter and Quintessence
Authors: Winterberg F.
Published: February 2015

According to the Planck aether hypothesis, the vacuum of space is a superfluid made up of Planck mass particles, with the particles of the standard model explained as quasiparticle - excitations of this superfluid. Astrophysical data suggests that ≈70% of the vacuum energy, called quintessence, is a negative pressure medium, with ≈26% cold dark matter and the remaining ≈4% baryonic matter and radiation. This division in parts is about the same as for rotons in superfluid helium, in terms of the Debye energy with a ≈70% energy gap and ≈25% kinetic energy. Having the structure of small vortices, the rotons act like a caviton fluid with a negative pressure. Replacing the Debye energy with the Planck energy, it is conjectured that cold dark matter and quintessence are Planck mass rotons with an energy below the Planck energy.
Two-dimensional Exchange and Nutation Exchange Nuclear Quadrupole Resonance Spectroscopy
Authors: Maćkowiak M. , Sinyavskya N. , Nikolaeva D.
Published: February 2015

A theoretical treatment of the 2D exchange NQR pulse sequence is presented and applied to a quantitative study of exchange processes in molecular crystals. It takes into account the off-resonance irradiation, which critically influences the spin dynamics. The response to the threepulse sequence of a system of spins I = 3/2 in zero applied field, experiencing electric quadrupole couplings, is analysed. The mixing dynamics by exchange and the expected cross-peak intensities as a function of the frequency offset have been derived. The theory is illustrated by a study of the optimization procedure, which is of crucial importance for the detection of the cross- and diagonal-peaks in a 2D-exchange spectrum. The systems investigated are hexachloroethane and tetrachloroethylene. They show threefold and twofold reorientational jumps about the carbon-carbon axis, respectively. A new method of direct determination of rotational angles based on two-dimensional nutation exchange NQRspectroscopy is proposed. Themethod involves the detection of exchange processes through NQR nutation spectra recorded after the mixing interval. The response of a system of spins I = 3/2 to the three-pulse sequence with increasing pulse widths is analyzed. It is shown that the 2D-nutation exchange NQR spectrum exhibits characteristic ridges, which manifest the motional mechanism in a model-independent fashion. The angles through which the molecule rotates can be read directly from elliptical ridges in the 2D spectrum, which are also sensitive to the asymmetry parameter of the electric field gradient tensor.
The Frequency Offset Effects of NQR of Spin I = 1 for Remote Detection
Authors: Mozjoukhine G. V.
Published: February 2015

The frequency offset effects of the signal interference during steady-state pulse sequences for remote nuclear quadrupole resonance (NQR) of 14N nuclei were investigated for the purposes of optimization in remote NQR. The experimental investigations with the separation of interfering NQR signals in sequences for observing signals {α0° |β90° −τ−α180° |β90° −τ} and {α0° |β90° −τ−α0° |β270° −τ} were carried out. The applications of the spherical tensor method for pure NQR of spin I = 1 for the investigation of these sequences and one pulse sequence, two pulse sequences are presented, too.
Powder Zeeman NQR Study on 123Sb in Sb(C6H5)3
Authors: Ege O. , Maekawa S. , Negita H.
Published: February 2015

Powder Zeeman NQR spectra of 123Sb in Sb(C6H5)3 were studied by means of a computer simulation and an experiment. The 123Sb nucleus has spin 7/2. There are two non-equivalent 123Sb atoms in the crystal of Sb(C6H5)3, so that there are two series of three transition lines (higher series: ν1h, ν2h, ν3h; lower series: ν11, ν21, v31). The powder Zeeman spectra for ν1h, based on the transition between the levels mI = ±1/2 and ±3/2, were observed at 77 K under the two conditions that i) the oscillation coil and the static magnetic coil were set coaxially and parallel, and ii) they were set perpendicular to each other. The powder line shapes for ν1h, which is the lowest line of the higher series due to 123Sb nuclei, were in good agreement with those from a computer simulation under the conditions i) and ii), showing that the asymmetry parameter of the field gradient is very small (η = 0). The line shape from i) exhibits two shoulders (saddle type), as it appeared for nuclear spin 5/2 and η = 0. The quadrupole coupling constant for 1h, calculated from the resonance frequency 47.820 MHz and the observed η, is 669.480 MHz at 77 K.
Pure NQR Quantum Computing
Authors: Furman G. B. , Goren S. D.
Published: February 2015

It is shown that pure NQR can be utilized as a platform for quantum computing without applying a high external magnetic field. By exciting each resonance transition between quadrupole energy levels with two radio-frequency fields differing in phase and direction, the double degeneracy of the spin energy spectrum in an electric field gradient is removed. As an example, in the case of I = 7/2 (nuclei 133Cs or 123Sb) the energy spectrum has eight levels which can be used as three qubits.
Conformational Structure of Chloromethyldichlorophosphines
Authors: Romanenko Evgenii A. , Nesterenko Alexander M.
Published: February 2015

I

The 35Cl nuclear quadrupole resonances (77 K) and ab initio calculations of trichloromethyldichlorophosphine () show that it exists in the chess conformation form. The barrier to internal rotation about the P-C bond in I at the RHF/6-31++ G(d,p) level equals to 38.1 kJ mol-1. In chloromethyldichlorophosphine (II) the extension of the basis set up to the RHF/6-311++G(df, pd) level does not improve the description of the most preferable gauche-conformation; only if electron correlation (at the MP2 level) is taken into account the results are in a good agreement with experimental data.
Temperature Dependence of 2H Nuclear Quadrupole Interaction in Very Short Hydrogen Bonds in Some Organic Acidic Salt Crystals
Authors: Miyakubo K. , Nakamura N.
Published: February 2015

The 2H nuclear quadrupole interaction parameters, e2Qq/h and η, are closely related to the shape of the potential energy surface at hydrogen bonds and depend sensitively on their geometry. We measured the temperature dependence of the 2H NMR spectra of the crystalline acidic salts KDCO3, KD cetylenedicarboxylate, RbD acetylenedicarboxylate, and KD maleate, which contain very short O-D···O type hydrogen bonds. The temperature coefficient decreases with increase in the O···O distance in the hydrogen bond. Ab inito molecular orbital calculations of the electric field gradient tensor based on the temperature dependent structure of each crystal indicate that thermal expansion of the hydrogen bond geometry is not responsible for this tendency. Ab initio calculations also predict that a fictitious off center shift of the hydrogen position in a symmetric hydrogen bond causes very high e2 Qq/h values. This suggests that low energy vibrational excitation may be responsible for large positive d (e2 Qq/h)/dT values in symmetric hydrogen bonds.
NMR Cross-Relaxation Study of Ultraslow Motion of the DomainWall in Channel Inclusion Compound
Authors: Panich A.M. , Krieger J. H. , Semenov A. R. , Chekhova G. N.
Published: February 2015

We report on an NMR study of ultraslow motions in the channel thiourea-hexachloroethane inclusion compound, [2.95(NH2)2CS] C2Cl6. Temperature dependent 1H NMR relaxation measurements of the powder thiourea-hexachloroethane at different resonance frequencies, from 23 to 55.5 MHz, have been carried out. Significant reduction of the spin-lattice relaxation time at 38 and 47 MHz is caused by the cross-relaxation of protons via the quadrupole chlorine nuclei. We show that the effective 1H-35Cl cross-relaxation observed in a powder sample is due to a slow mode process, when the molecules of the domain wall exhibit a correlated translational and rotational motion over the channel. Such propagation of the domain wall is confirmed by atom-atomic potential calculation. - Pacs: 76.60-k, 76.60.Es, 61.44.Fw, 61.66.Hq
85,87Rb, 14N NMR Studies of Successive Phase Transitions and Incommensurate Phase in R2Pb[Cu(NO2)6] (R = NH4, Rb)
Authors: Ishikawa Hiroyuki , Mizuno Motohiro , Suhara Masahiko
Published: February 2015

85,87Rb and 14N NMR spectra and spin-lattice relaxation time (T1) were measured for R2Pb[Cu(NO2)6] (R = Rb, NH4). The quadrupole coupling constant (e2Qq/h), asymmetry parameter (η), and the effective transverce relaxation time (T2) were estimated from the simulation of NMR spectra. The NMR spectra in commensurate phase III can be explained by the superposition of two components corresponding to two inequivalent sites of the R+ ion. In the incommensurate phase II, e2Qq/h and T2 decreased with increasing temperature, while was almost temperature independent. T1 in phase II is found to be determined by the contribution of acoustic phason with multi-soliton limits
Restricted Rotational Motion of InterlayerWaterMolecules in Vanadium Pentoxide Hydrate, V2O5·n D2O, as Studied by Deuterium NMR
Authors: Takeda Sadamu , Gotoh Yuko , Maruta Goro , Takahara Shuichi , Kittaka Shigeharu
Published: February 2015

The rotational behavior of the interlayer water molecules of deuterated vanadium pentoxide hydrate, V2O5.nD2O, was studied by solid-state deuterium NMR for the mono- and double-layer structures of the adsorbed water molecules. The rotational motion was anisotropic even at 355 K for both the mono- and double-layer structures. The 180° flipping motion about the C2-symmetry axis of the water molecule and the rotation around the figure axis, which makes an angle Ɵ with the C2-axis, occurred with the activation energy of (34±4) and (49±6) kJmol-1, respectively. The activation energies were almost independent of the mono- and double-layer structures of the water molecules, but the angle Ɵ made by the two axes varied from 33° for the monolayer to 25° for the double-layer at 230 K. The angle started to decrease above 250 K (e. g. the angle was 17 at 355 K for the double-layer structure). The results indicate that the average orientation of the water molecules in the two dimensional interlayer space depends on the layer structure and on the temperature. From the deuterium NMR spectrum at 130 K, the quadrupole coupling constant e2Qq/h = 240 kHz and the asymmetry parameter η= 0.12 were deduced. These values indicate the average hydrogen bond distance R(O H) = 2.0 Å for the D2O molecules in the 2D-interlayer space
11B NMR Study of CexLa1–xB6
Authors: Magishi K. , Kawakami M. , Saito T. , Koyama K. , Mizuno K. , Kunii S.
Published: February 2015

We have carried out 11B NMR experiments on single crystals of CexLa1-xB6 in order to investigate the nature of phase IV. The NMR spectrum undergoes an appreciable broadening by the internal magnetic field as is lowered in phase IV, and the nuclear spin-lattice relaxation rate, 1/T1, exhibits a sharp peak around the phase I-IV boundary. Also, in phase III the amplitude of the antiferromagnetic (AFM) moment is large enough even just below the phase IV-III transition, which suggests that the AFM moment grows considerably in phase IV. These results support the view that phase IV is an AFM ordered phase
1H, 2H and 13C NMR Studies of Cation Dynamics in a Layered Perovskite-Type Incommensurate Compound (n-C3H7NH3)2CdCl4
Authors: Suzuki Koh-ichi , Fujimori Hiroki , Asaji Tetsuo , Ishimaru Shin’ichi , Ikeda Ryuichi
Published: February 2015

Cation dynamics in (n-C3H7NH3)2CdCl4 and (n-C3H7ND3)2CdCl4 were investigated by 1H, 2H, and 13C NMR measurements. An overall motion of the cation being associated with the fluctuation of the molecular axis is suggested to be activated with increasing temperature. The cationic motion is enhanced at the counter side of the -NH3
+ group probably because the group is bound with the inorganic layer through the N-H...Cl hydrogen bonds
133Cs NMR Spin-Lattice Relaxation Time and Chemical Shift Studies on Cs2MX4 Crystals with Sr2GeS4 and β-K2SO4 Structures Performing no Low Temperature Phase Transition
Authors: Suzuki Koh-ichi , Ishimaru Shin’ichi , Ikeda Ryuichi
Published: February 2015

133Cs NMR spectra and spin-lattice relaxation times T1 in crystalline Cs2ZnCl4 and Cs2ZnBr4 with -K2SO4 structure, and Cs2CdI4 and Cs2HgI4 with Sr2GeS4 structure, which have no phase transition in the lower temperature regions, weremeasured to clarify the relation between the interionic covalency and crystal structures. Two central lines corresponding to two crystallographically inequivalent Cs sites were observed in all compounds. One of the two peaks in β-K2SO4-type compounds appears below 40 ppm, but another peak in those compounts and the both lines in Sr2GeS4-type compounds show larger shifts, 130 - 200 ppm. The temperature dependences of T1 observed in Sr2GeS4-type compounds were close to the theoretical behaviour, calculated by considering contributions from normal lattice vibrations. Deviations from the calculation obtained for β-K2SO4-type systems are attributable to the difference in interionic interactions, i. e., partial covalency, in the crystals
Hydration in Alkali-silicate Glasses Studied by Two Dimensional Multi-Quantum Magic Angle Spinning
Authors: Masui Hirotsugu , Chen Danping , Akai Tomoko , Yazawa Tetsuo
Published: February 2015

The hydration in Na2O-3SiO2 glass was studied by 23Na Magic Angle Spinning (MAS) and 2D MQMAS NMR spectroscopy. It was found that one-dimensional MAS spectra for the hydrated glasses with more than 8.4 wt% water consist of two signals at around -10 and -40 ppm. On the other hand, anhydrous glass and glass with low water content (2.8 wt%) give a single resonance line at around -10 ppm. From 2D MQMAS spectra, the isotropic chemical shift ( δiso) and the quadrupole coupling frequency (VQ) for two sites (Na(1) and Na(2)) were estimated: δiso = 4.2 ppm and VQ = 0.6 MHz for Na(1) and δiso = 10.2 ppm and VQ = 1.3 MHz for Na(2). These results are discussed together with our previous results of 29Si and 1H NMR, and infrared spectra. It is speculated that Na(1) may exist in a similar environment as that in anhydrous sodium-silicate glasses, while Na(2) may be attached directly to water molecules
Charging Effects of Vortex Core in High Temperature Superconductors Probed by Nuclear Quadrupole Interaction
Authors: Kumagai Ken-ichi , Kakuyanagi Kosuke , Nozaki Koji , Matsuda Yuji
Published: February 2015

From high resolution measurements of the nuclear quadrupole frequencies we obtain experimental evidence that a vortex in high Tc superconductors (HTSC) traps a finite electric charge. In slightly overdoped YBa2Cu3O7 the vortex is negatively charged by trapping electrons, while in underdoped YBa2Cu4O8 it is positively charged by expelling electrons. The sign of the trapped charge is opposite to the sign predicted by the conventional BCS theory. Moreover, in both materials the deviation of the magnitude of the charge from the theory is significant. These features can be attributed to the novel electronic structure of the vortex in HTSC
Distribution of Electric Field Gradient at Aluminum Sites in Zeolite Loaded with Potassium
Authors: Igarashi M.
Published: February 2015

In the zeolite LTA, loaded with potassium, the temperature and field dependence of 27Al NQR was observed. Symmetrical single shoulders are found on both sides of the central line. The shape and the shift of those shoulders show no dependence on both temperature and the strength of the external field. This evidences a first order electric quadrupolar shift, being the result of the distribution of the nuclear quadrupole coupling constant and the asymmetry parameter at 27Al sites
139La NQR Study in La2CuO4 over Temperatures up to 800 K
Authors: Matsumura M. , Yamagata H. , Yasuoka H. , Ueda Y.
Published: February 2015

We have measured 139La NQR spectra and the nuclear spin-lattice relaxation rate for the highest (±7/2↔±5/2) and the middle (±5/2↔±3/2) NQR lines in the parent compound of high-Tc superconductor, La2CuO4, in a wide temperature range up to 800 K. From the abrupt increase of the quadrupole frequency VQ just below the tetra-ortho structural transition temperature TOT which comes from the staggered tilt of the CuO6 octahedra, the critical exponent is evaluated to be 0.4 which is close to 0.5 expected β in the standard mean field approximation for second order phase transition. In higher temperature than TOT, the nuclear spin-lattice relaxation at La site is dominated by the quadrupole relaxation, not reflecting the critical spin dynamics in the CuO2 plane. We successfully discriminate the two types of quadrupole relaxation rate, WQ1 and WQ2. The relaxation rate WQ2 is one order of magnitude larger than 1 and increases with the critical exponent α ⁓1.19 toward TOT
51V NMR Study of a C15 Laves Phase Compound HfV2
Authors: Kishimoto Yutaka , Ohno Takashi
Published: February 2015

We analyzed the K-x plot in order to investigate the change in the electronic state in the C15 Laves phase compound HfV2 at the lattice transformation temperature TL (~120 K). We could obtain K3d orb X3d orb, and X5d orb + (2/3) XPauli + Xdia, which are consistent with those reported in our previous paper, and discussed the changes in density of states of the V3d and 4s electrons at TL.

For the superconducting state we discussed the d wave Anderson-Brinkman-Morel (ABM) type energy gap in which the gap is anisotropic and vanishes at points on the Fermi surface
Theory of 14N and 17O Nuclear Quadrupole Interactions in Polyglycine and Glycine in the Protein Chain of Cytochrome c
Authors: Scheicher R. H. , Cammarere D. , Sahooa N. , Nagamine K. , Das T. P.
Published: February 2015

As part of our ongoing investigations on hyperfine properties of nuclei and attached probes (like muon and muonium) in the protein chain of Cytochrome c (Cyt c), we have been studying the 14N and 17O nuclear quadrupole interactions in the amino acids in the protein chain at different sites where they occur. As a specific example of one of the amino acids in this context, we shall present our results on Glycine in the homo-molecular polymer Polyglycine and expectations for the hetero-molecular environment occurring at a particular region of the protein chain of Cyt c which is far enough away from the heme unit to make the results more characteristic of the chain.

In the Polyglycine polymer, our results for the 14N and 17O coupling constants e2qQ and asymmetry parameters for a central Glycine in a chain of odd numbered molecules are used to study how the e2qQ and vary with the chain length and to compare with the results for the isolated Glycine molecule. The aim is to study the convergence of the results with respect to chain length to find out the appropriate length at which the results become characteristic of the polymer chain. This conclusion is expected to provide insights into the chain length to be used in the protein to simulate the results for the protein chain in Cyt c. The Hartree-Fock Cluster procedure is being used for the investigations for all the results to be reported
Theory of 14N and 17O Nuclear Quadrupole Interactions in the Single Amino Acids Occurring in the Protein Chain of Cytochrome c
Authors: Scheicher R. H. , Cammarere D. , Sahoo N. , Nagamine K. , Das T. P.
Published: February 2015

The understanding of electron transport in proteins based on a novel technique involving muon spin rotation (μSR)measurements is a topic of great current interest. The technique, which involves study of spin relaxation of a positive muon (μ+) trapped in amino acids in protein chains due to the fluctuating magnetic field that the moving electron produces, is based on the premise that the electron is generated by ionization of a muonium (Mu) which was trapped at the same site as the μ+ left behind. In attempting to test this premise from first-principles for the Cytochrome c (Cyt c) system in which recent μSR measurements have been made, we have carried out Hartree- Fock investigations of the electronic structures of the bare amino acids and amino acids with + and Mu trapped at the oxygen of the C=O group common to all amino acids. With the aim that the comparison of theoretically predicted experimental nuclear quadrupole interaction (NQI) parameters will provide a useful test of the electron distribution in the amino acids of Cyt c, we present results for the nuclear quadrupole coupling constants (e2qQ) and asymmetry parameters (η) for the bare amino acids and the amino acids with trapped μ+ and Mu. The trends in 2 and for 14N and 17O between the various amino acids, as well as the changes in these parameters in the presence of μ+ and Mu are being analyzed. It would be helpful to have experimental data for e2qQ and to η compare with our predictions for the amino acids as they occur in vitro in polycrystalline Cyt c in which the SR measurements have been carried out. It is also hoped that the μSR technique will be able to provide experimental data on e2qQ and for the 14N and 17O nuclei to compare with our predictions
Density Functional Theory Studies of Bonding in Complexes H3N···XY of Ammonia and Dihalogen Molecules: A Comparison with Experimental Results from Rotational Spectroscopy
Authors: Poleshchuk O. Kh. , Legona A. C.
Published: February 2015

The electron density and nuclear quadrupole coupling constants (NQCC) of the H3N...XY (n a type in Mulliken notation) complexes, (X, Y = F, Cl, Br and I), are analyzed with the aid of density functional calculations. To demonstrate the quality of the calculations, various bond lengths and NQCCs obtained by using the hybrid Becke-Lee-Perdew-Yang functional are compared with the corresponding experimental values determined from rotational spectroscopy. An analysis of the NQCC values and various quantities derived fromthe natural bond orbital approach reveals that the molecular interaction is mainly electrostatic, with probably only a small extent of intermolecular electric charge redistribution on complex formation
EFGs on Surfaces – Experiment and Theory
Authors: Lindgren Bengt
Published: February 2015

Experimental and calculated electric field gradients (EFG) on various probe atoms at different sites on metal surfaces, are reviewed. The calculations are based on the discrete variational method (DVM) molecular/cluster approach within the local density approximation and the experimental data are mostly obtained with the time differential perturbed angular correlation (TDPAC)method. Recent observations of an increasing EFGwith temperature for adsorbed Se on (111) metal surfaces are explained as due to an outward probe relaxation, resulting in an increased EFG. This means that positive EFGs at (111) sites increase whereas negative EFGs at (001) surfaces reduce inmagnitude. Previously unpublished results for various Cd-probe sites at Pd(110) are also discussed in detail
Quadrupole Interactions of the Short-lived -Emitter 16N in TiO2
Authors: Minamisono T. , Matsuta K. , Miyake T. , Minamisono K. , Mihara M. , Fukuda M. , Sato K. , Zhu S.Y.
Published: February 2015

Quadrupole interactions of 12,14N in BN(hexagonal) crystal were studied by detecting β-NQR of 12N and FT-NMR of 14N, respectively. β-NMR of 16N(Iπ= 2-, T1/2 = 7.13 s) in MgO crystal was detected to determine the magnetic moment to be |μ(16N: 2 )| = (1.986±0.001) μN. Also, the β-NQR’s of 12,16N in TiO2 crystal were detected to be |Q(16N: 2-)| = (17.9± 1.7) mb. An abnormally small effective charge for neutrons is required to account for

|Q(16N: 2-)|.
I-129 and Au-197 Mössbauer Spectroscopy of AuI and AgAuI2
Authors: Sakai H. , Nakashima S. , Moriwaki T. , Yamada K. , Maeda Y.
Published: February 2015

Mössbauer spectroscopy of 129I and 197Au nuclei has been applied for AuI and AgAuI2 to clarify the electronic structures of the gold and iodine atoms, and to investigate the nature of the Au-I bonds. In the 129I Mössbauer spectra the sign of e2qQ is positive for AuI, whereas the sign is negative for AgAuI2. This is attributable to the difference in molecular structures: The iodine atom in AuI is bridged by two gold atoms and in AgAuI2 the iodine is terminal. The 197Au Mössbauer spectra suggest that the Au-I bond in AgAuI2 is more covalent than that in AuI. We have revealed that AgAuI2 consists of Ag+ and linear [I-Au-I]- units from the Rietveld refinement of the X-ray powder diffraction pattern
155Gd Mössbauer Spectroscopic Study of GdM(CN)6 · 4H2O (M = CrIII, FeIII and CoIII) and KGdM(CN)6 · 3H2O (M = FeII and RuII)
Authors: Wang Junhu , Abe Junko , Kitazawa Takafumi , Takahashi Masashi , Takeda Masuo
Published: February 2015

155Gd Mössbauer spectroscopic studies of the title complexes have been performed. Although the 155Gd isomer shifts (d) varied scarcely, the quadrupole coupling constants (e2qQ) changed in the range 4.07-4.81 mm s-1. The e2qQ values of KGdM(CN)6 · 3H2O (M = FeII and RuII) are larger than those of GdM(CN)6 · 4H2O (M = CrIII, FeIII, and CoIII), these values increasing with increasing orthorhombic distortion of the crystal structures. A relationship between the e2qQ values and the ionic radii of the transition metal ions has also been recognized
Static Electric Quadrupole Moments in the Ground State and K = 4–
1 Bands in 168Er
Authors: Thakur P. , Behra M. S. , Dogra R. , Bhati A.K. , Bedi S. C.
Published: February 2015

The time differential perturbed angular correlation (TDPAC) technique has been used to study the nuclear quadrupole interactions of the first excited state of ground state rotational band (2+, 80 keV, T1/2 = 1.88 ns) and the band head of the = 41
- band (41
-,1094 keV, T1/2 = 120 ns) in the 168Er nucleus of a polycrystalline Er host. At room temperature we obtained the electric quadrupole interaction frequencies ω0(K= 0) = 457(15) Mrad/s and ω0(K= 4) = 69(2) Mrad/s, respectively, for the 2+ and 4- isomeric states of 168Er. The ratio of the spectroscopic quadrupole moments, i. e. Qs (K= 4)/Qs (K= 0) = 0.69(3), is independent of any model approximation and the electric field gradient at 168Er in the host metal
Lattice Sites of Cd in Ferroelectric BaTiO3`
Authors: Dietrich M. , Camard C. , Deicher M. , Richter F. , Samokhvalov V. , Unterricker S.
Published: February 2015

The radioactive isotope 111mCd was implanted into BaTiO3 in order to measure electric field gradients (EFGs) with Perturbed Angular Correlation spectroscopy (PAC). It is possible to anneal the implantation induced lattice damage to a certain extent. Then, 111mCd probes are positioned at two sites with distinct axially symmetric EFGs characterized by the quadrupole coupling constants of 33.9(9) and 69.8(9) MHz. These EFGs can be assigned to 111mCd at the Ti- and the Ba-sites
Lattice Locations of 12B in CaB6
Authors: Mihara M. , Hashimoto K. , Arimura K. , Kudo S. , Akutsu K. , Minamisono K. , Miyake T. , Fukuda M. , Matsuta K. , Minamisono T.
Published: February 2015

The nuclear quadrupole interaction of the short-lived -emitter 12B implanted into CaB6 crystal has been studied by means of modified β-NMR (β-NQR) technique. The electric field gradient at the implanted 12B was found to be = q-(1.34±0.05)x1021 V/m2 at room temperature. From this result it is concluded that the 12B probe nuclei are mainly implanted in the substitutional boron site and are applicable to systematic NMR studies of ferromagnetic La doped CaB6
121Sb Mössbauer Spectra of Hypervalent Complexes Having an Antimony-transition Metal Bond and Partial Quadrupole Coupling Constants
Authors: Takahashi Masashi , Ishiguro Atsushi , Maeda Masaki , Takeda Masuo , Toyota Koichiro , Yamamoto Yohsuke , Akiba Kin-ya
Published: February 2015

Antimony-121 Mössbauer spectra for hypervalent pentacoordinate antimony compounds having Sb-transition metal bond [Rf2SbMCp(CO)n {RfH = o-C6H4C(CF3)2OH- , M = Fe, Ru, Cr,Mo, W}, Rf2SbFeCp(CO)PPh3, Rf2SbFeCp(dppe)] and closely related compounds Rf2SbTol (Tol = p-CH3C6H4), Rf2SbX (X = Cl, Br) are described. The strong -donor power of the metal fragments is demonstrated by theM¨ossbauer parameters. The -donor power decreases in the order FeCp(dppe) > FeCp(CO)PPh3 > FeCp(CO)2 > RuCp(CO)2 > CrCp(CO)3 > MoCp(CO)3 > WCp(CO)3 ≫Tol. The essential trends in the molecular structure and the Berry pseudorotation are interpreted by this order. In addition, the e2qQ values for 32 hypervalent antimony compounds are successfully calculated using the additivity model for the e2qQ value. A unique electronic feature for Rf2SbX is clarified through the calculation
Photoswitching of the Optical and Electrical Properties of One-dimensional π-Electron Systems
Authors: Tyutyulkov Nikolai , Wilhelm-Ostwald Fritz Dietz
Published: February 2015

The photoswitching of the energy gap width of the isomeric forms of photoresponsive polymers with homonuclear photochromic diarylethene elementary units is investigated theoretically, taking into account the correlation correction. It is shown that a real switching of electrical conductivity (insulator ⇔ semiconductor or conductor) can not be realized with polymers with alternant homonuclear π-electron systems within the elementary unit. A change and tuning-in of the light absorption is possible in most cases.
The Investigation of Phase Diagrams of Erbium Pnictides
Authors: Abdusalyamova M. N. , Rachmatov O. I.
Published: February 2015

The phase diagrams of Er-Sb and Er-Bi have been obtained. Erbium forms three compounds with antimony as well as bismuth. The antimonides and bismuthides Er5Sb3 (1640°C), Er5Bi3 (1427°C), ErSb2 (650°C) and ErBi2 (595°C) are formed by peritectic reactions. ErSb (2040°C) and ErBi (1860°C) melt congruently.
The Terbium-Bismuth Alloy System
Authors: Abdusalyamova M. N. , Rachmatov O. I.
Published: February 2015

The phase diagrams of Tb-Bi has been obtained. A peritec reaction develops as a result of bismuth addition, the transformation temperature of terbium being lowered by 18°C. Eutec reactions occur at 17 at.%Bi and 1090°C, and at more than 99 at.%Bi and 269°C. There are four compounds in the system: Tb5Bi3, Tb4Bi3, TbBi, and TbBi2, resulting from peritectic reactions at 1480, 1570, 1770 and 720°C. While TbBi melts congruently at 1920°C. Tb5Bi3 and TbBi were observed to exhibit transformation.
Quantum Numbers of Eigenstates of Generalized de Broglie-Bargmann- Wigner Equations for Fermions with Partonic Substructure
Authors: Stumpf H.
Published: February 2015

Generalized de Broglie-Bargmann-Wigner (BBW) equations are relativistically invariant quantum mechanical many body equations with nontrivial interaction, selfregularization and probability interpretation. Owing to these properties these equations are a suitable means for describing relativistic bound states of fermions. In accordance with de Broglie’s fusion theory and modern assumptions about the partonic substructure of elementary fermions, i.e., leptons and quarks, the three-body generalized BBW-equations are investigated. The transformation properties and quantum numbers of the three-parton equations under the relevant group actions are elaborated in detail. Section 3 deals with the action of the isospin group SU(2), a U(1) global gauge group for the fermion number, the hypercharge and charge generators. The resulting quantum numbers of the composite partonic systems can be adapted to those of the phenomenological particles to be described. The space-time transformations and in particular rotations generated by angular momentum operators are considered in Section 4. Based on the compatibility of the BBW-equations and the group theoretical constraints, in Sect. 5 integral equations are formulated in a representation with diagonal energy and total angular momentum variables. The paper provides new insight into the solution space and quantum labels of resulting integral equations for three parton states and prepares the ground for representing leptons and quarks as composite systems.
Chaotic Amplification in the Relativistic Restricted Three-body Problem
Authors: Wanex Lucas F.
Published: February 2015

The relativistic equations of motion for the restricted three-body problem are derived in the first post-Newtonian approximation. These equations are integrated numerically for seven different trajectories in the earth-moon orbital system. Four of the trajectories are determined to be chaotic and three are not chaotic. Each post-Newtonian trajectory is compared to its Newtonian counterpart. It is found that the difference between Newtonian and post-Newtonian trajectories for the restricted three-body problem is greater for chaotic trajectories than it is for trajectories that are not chaotic. Finally, the possibility of using this Chaotic Amplification Effect as a novel test of general relativity is discussed.
Two New Applications of the Modified Extended Tanh-Function Method
Authors: Elwakil S. A. , El-labany S. K. , Zahran M. A. , Sabry R.
Published: February 2015

Based on a modified extended tanh-function method and symbolic computation, new exact solutions are found for a soliton breaking equation and coupled kdv system. The obtained solutions include rational, soliton, singular and periodical solutions.
Conformational Phase Transitions Associated with Reversal of Hydrogen Bond Direction in 4-Chloro- and 4-Bromobenzyl Alcohols. An X-Ray Study
Authors: Hashimoto Masao , Harada Michiko
Published: February 2015

Notable changes in the molecular conformations of 4-chlorobenzyl alcohol around the C(H2)-Car and O-C(H2) bonds were found to take place at the first-order phase transition point (Tc1 = 236 K). Quite similar phenomena were observed at Tc1 (217 K) of the isomorphic 4-bromo compound. The two kinds of conformational changes are considered to couple and cause the reversal of the direction of the linear O-H. . . O hydrogen bond as the compound undergoes the first-order transition. The CH2OH moiety participates in several short intermolecular contacts, and a C-H. . .π interaction exists between the CH2 and the neighboring phenyl group. These intermolecular factors seem to contribute to the regulation of the molecular conformation in the crystal. The C-O bond length of each compound shortens considerably at T > Tc1.
Emission Anisotropy of p-Cyano-N,N-Dialkylanilines in Poly(vinyl alcohol) Film
Authors: Kawski A. , Bojarski P. , Kukliński B.
Published: February 2015

The emission anisotropy spectra, r, (λ ) of p-cyano-dimethylaniline (CDMA) and p-cyano-diethylaniline (CDEA) in PVA films are temperature dependent. At 296 K a characteristic dependence of r, (λ ) on the absorption (A), short emission (SE) and long emission (LE) band, responsible for the total emission of fluorescence and phosphorescence is observed. On temperature enhancement to 355 K and next to 380 K the phosphorescence is eliminated. In the case studied the emission anisotropy is positive for the fluorescence bands SE and LE and it attains approximately 0.2, confirming thus that the transition moments’ directions are in these bands parallel.
A Central Force Oscillating in Time Caused by a Linear Change in Time of the Magnetic Induction
Authors: Olszewski S.
Published: February 2015

A charged particle in its planar motion in a constant magnetic field is submitted a centripetal force acting on that particle. The amplitude of this force is constant in time. In this paper it is demonstrated that by a linear change in time of the magnetic induction another centripetal force acting on the particle is created. This force has an amplitude oscillating in time with the frequency equal to that of the particle gyration.
Nonequilibrium Dynamics and Magnetoviscosity of Moderately Concentrated Magnetic Liquids: A dynamic Mean-field Study
Authors: Ilg Patrick , Hess Siegfried
Published: February 2015

A mean-field Fokker-Planck equation approach to the dynamics of ferrofluids in the presence of a magnetic field and velocity gradients is proposed that incorporates magnetic dipole-dipole interactions of the colloidal particles. The model allows to study the combined effect of a magnetic field and dipolar interactions on the viscosity of the ferrofluid. It is found that dipolar interactions lead to additional non-Newtonian contributions to the stress tensor, which modify the behavior of the non-interacting system. The predictions of the present model are in qualitative agreement with experimental results, such as the enhancement as well as the different anisotropy of the magnetoviscous effect and the dependence on the symmetric velocity gradient.
Autocatalytic Fusion-Fission Burn in the Focus of Two Magnetically Insulated Transmission Lines
Authors: Winterberg F.
Published: February 2015

A configuration made up of two nested magnetically insulated transmission lines, the inner one carrying a high voltage lower current - and the outer one a high current lower voltage - pulse, was in a previous communication proposed for the ignition of a magnetic field assisted thermonuclear detonation wave. Unlike the fast ignition concept, it does not require the compression of the DT fusion fuel to densities in excess of the solid state. Here I show that with the same configuration, but by surrounding the DT fusion fuel with a blanket of solid U238, Th232 or B10, the ignition of a thermonuclear detonation wave is possible with densities of the DT fuel less than solid state densities, because the DT fusion neutrons can make a sufficient number of fission reactions, greatly increasing the pressure in the blanket, compressing the DT to high densities, launching a magnetic field assisted thermonuclear detonation wave. This autocatalytic fusion-fission burn has the further advantage that it can burn natural uranium, thorium and even boron.
The Relationship between Lennard-Jones (12-6) and Morse Potential Functions
Authors: Lim Teik-Cheng
Published: February 2015

The most commonly used potentials for van der Waals interactions are the Exponential-6 and the Lennard-Jones (12-6) potential. In this paper a correlation between them is described. The Morse function, which is normally applied for quantifying 2-body interactions, has been adopted in one software. This paper deals with the validity of the Morse function for non-bonded interactions by means of obtaining a relationship between the Morse and the Lennard-Jones (12-6) potential functions. An approximate and an exact mathematical relationship is demonstrated to exist between these two potentials.
Crystal Structure and Cationic Motion of o-Toluidinium Chloranilate and m-Toluidinium Chloranilate Studied by X-ray Diffraction and 1H NMR
Authors: Fukunaga Takeo , Kumagae Naoki , Ishida Hiroyuki
Published: February 2015

The crystal structure of o-toluidinium chloranilate and m-toluidinium chloranilate, 2CH3C6H4-NH3
+ · C6O4Cl2
2−, was determined by single crystal X-ray diffraction at room temperature. It was found that o-toluidinium chloranilate (I) is monoclinic, P21/n (#14), Z = 2, a = 5.2184(14), b = 7.825(2), c = 22.840(5) Å , and β = 92.015(19)°, and m-toluidinium chloranilate (II) is monoclinic, P21/c (#14), Z = 2, a = 11.214(2), b = 5.4844(10), c = 16.379(6) Å, and β = 105.21(2)°. In these salts, the cations are connected with the anions by N-H... O hydrogen bonds to form 2:1 units of 2CH3C6H4NH3
+ · C6O4Cl2
2− that are located on inversion centers. The 2CH3C6H4NH3
+ · C6O4Cl2
2− units in both salts are connected by other N-H... O hydrogen bonds to build a three-dimensional hydrogen-bond network. Motions of the toluidinium ions in solid (I) and (II) were studied by 1H NMR spin-lattice relaxation time measurements. Reorientations of the NH3
+ group about the C-N bond axis and the CH3 group about the C-C bond axis were observed, and their motional parameters were evaluated. The internal rotational barriers of the NH3
+ and CH3 groups of an isolated o-toluidinium ion were estimated from ab initio molecular orbital calculations at HF/6-31G(d,p), MP2/6-31G(d,p), and B3LYP/6-31G(d,p) levels of theory.
Crystal Structure Studies on p-Substitutedbenzenesulphonamides 4-X-C6H4SO2NH2 (X = CH3, NH2 F, Cl or Br)
Authors: Thimme Gowda B. , Jyothi K. , Kožíšek Jozef , Fuess Hartmut
Published: February 2015

Effect of ring substitution on the crystal structures of p-substitutedbenzenesulphonamides, p-XC6H4SO2NH2 (X = F, Cl, Br, CH3 or NH2) has been studied by determining the crystal structures of 4-chlorobenzenesulphonamide (4-ClC6H4SO2NH2) and 4-bromobenzenesulphonamide (4-BrC6H4SO2NH2) and analyzing the results along with the structures of 4-methylbenzenesulphonamide (4-CH3C6H4SO2NH2), 4-fluorobenzene-sulphonamide (4-FC6H4SO2NH2) and 4-aminobenzenesulphonamide (4-NH2C6H4SO2NH2). The crystal type, space group, formula units and lattice constants in Å of new structures are: (4-ClC6H4SO2NH2); monoclinic, P21/n, Z = 4, a = 6.6276(10), b = 16.219(3), c = 7.5716(10), β = 93.387(14)°; (4-BrC6H4SO2NH2): monoclinic, P 21/n, Z = 4, a = 6.5660(10), b = 16.4630(10), c = 7.6900(10), β = 92.760(10)°. Orientation of the amine group with respect to the phenyl ring is given by the torsion angles C(2)-C(1)-S-N: 70.9° and C(6)-C(1)-S-N: −108.5°. Similarly, the orientation of S, O(1) and O(2) with respect to the ring are given by torsion angles. The comparison of bond lengths and bond angles of 4-fluoro-, 4-chloro-, 4-bromo-, 4-methyl- and 4-amino-benzenesulphonamides reveal that the S-N and C-S bond lengths decrease with the introduction of electron-withdrawing substituents such as F, Cl or Br, while these groups do not have significant effects on the S-O distances. The effect on ring C-C distances was not uniform. Substitution of F, Cl or Br decreases the O-S-N bond angle, but increases the O-S-N, N-S-C(1) and C(3)-C(4)-C(5) bond angles.
New Solitary-wave Solutions for the Higher Order Nonlinear Schrödinger Equation with Both Real and Imaginary Raman Terms
Authors: Hong Woo-Pyo
Published: February 2015

We find new solitary-wave solutions of the higher order nonlinear Schrödinger equation with both real and imaginary Raman terms, which can model an ultrashort pulse propagation through optical fibers, under some constraint among the model coefficients. The physical conditions such as the wavelength needed to launch the pulse, the types of optical fibers, and the required peak power, are obtained from the constraints for the solitary-wave solutions. - PACS number(s): 42.65.Tg, 42.81Dp, 02.30.Jr, 42.79.Sz.