bluuebunny/crossref_metadata_2025_split huggingface dataset:
Conformational Analysis of Chloromethylenimine and its Hydrogen-Bonded Dimers with Water from the Study of Nuclear Quadrupole Interactions
Authors: Sathyan N. , Santhanam V. , Sobhanadri J. 
Published: February 2015

Abstract
A molecular conformation study on N-Chloromethylenimine and its 1:1 dimeric form with water has been carried out using the ab-initio method at 6-31 G and 6-31 G* basis set. We consider the two most stable conformers of the N-chloromethylenimine -water binary mixture involving double hydrogen bonds. In all cases the proton affinity has been calculated. Each system considered in this work has the nuclear quadrupole interactions of the nitrogen and chlorine resonant nuclei which have been calculated and compared. It is found that the nuclear quadrupole coupling constant for the nitrogen nucleus increases in the hydrogen bonded complexes and decreases for the chlorine nucleus compared to the monomeric values. The influence of proton affinity is reflected in the nuclear quadrupole coupling constant.
35Cl NQR of the N-Cl Bond and the Modified Townes-Daily Theory
Authors: Dolgushin G.V. , Lazarev I.M. , Nikitin P.A. , Larina L.I. 
Published: February 2015

Abstract
The modified Townes-Daily equation is shown to be better than the original one for frequencies of compounds having N-Cl bonds. Of the three semi-empirical methods AM 1, MNDO, PM 3, the first is preferable. The asymmetry parameters for the same compounds have been evaluated. The 35Cl NQR frequencies of two tautomers of N-chlorobenzotriazole are compared.
Nuclear Quadrupole Interactions as a Probe of Glass Molecular Structure
Authors: Boolchand P. 
Published: February 2015

Abstract

125Te absorption and 129I emission Mössbauer spectroscopies have proved to be the methods of choice to probe chalcogen chemical order in condensed matter using nuclear quadrupole interactions. In chalcogenide glasses, the technique has been unusually rewarding in decoding both the elements of local atomic structures and those of the medium-range atomic structures.
Magnetic Resonances of 51V, 209Bi, Mn2+, and Fe3+in BiVO4Single Crystals
Authors: Choh Sung Ho 
Published: February 2015

Abstract
Nuclear magnetic resonance (NMR) of 51V and 209Bi, and electron paramagnetic resonance (EPR) of Mn2+ and Fe3+ impurities in ferroelastic BiVO4 single crystals are reviewed. The nuclear quadrupole parameters and principal axes of the two host nuclei, 51V and 209Bi, and the second-or-der zero field splitting tensor of the isoelectronic 3 d5 ions, Mn2+ and Fe3+ , in BiVO4 are determined for the first time. Temperature dependence studies on 51V NMR and Mn2+ EPR confirmed that this crystal undergoes a second order phase transition. The substitutional sites of Mn2+ and Fe3+ in BiVO4 are Bi3+ and V5+, respectively.
Chlorine Substituted Acetic Acids and Salts. Effect of Salification on Chlorine-35 NQR
Authors: David Serge , Gourdji Michel , Guibé Lucien , Péneau Alain 
Published: February 2015

Abstract
The NQR of a quadrupolar probe nucleus is often used to investigate the effect of substituent in molecules. The inductive effect, based on a partial charge migration along the molecular skeleton is the only one present in saturated aliphatics, the conjugative effect appearing in conjugated molecules, especially aromatics. As the stepwise charge migration mechanism, formerly used to explain the inductive effect, is now believed obsolete, we have wanted to reexamined the case of chlorine substituted acetic acids and salts. The data in literature was extended by observing reso-nances and determining NQR frequencies in several acids and salts. The present analysis of the salification of mono-, di-and tri-chloroacetic acids, which is equivalent to a deprotonation or the substitution of the acid hydrogen by a negative unit charge, shows that a model based on the polarization of the chlorine atom(s) by the carboxyle group is consistent with experimental results: the polarization energy appears to be proportional to the NQR frequency shifts; experimental data show a correlation between the NQR frequency shifts accompanying salification and the variations of the intrinsic acidity measured in the gas phase; this, in turn shows that there is a proportionality between the polarization energy and the variations in the acid free enthalpy of dissociation. From the comparison between fluorine, chlorine, bromine and iodine, it also appears that an alternative mechanism, the polarization of the carboxyl group by the halogen, would be important only in the case of the fluoroacetic acid.
125I NQR Spectra of Iodobenzoic Acid and Iodophenol Derivatives. H-Bonds and C-I Characteristic Bonds of These Substances
Authors: Babushkina T. A. , Goltyapin Yu. V. , Gushchin S. I. 
Published: February 2015

Abstract
This is a review of investigations on iodo-benzoic acid, iodohippuric acid, and iodophenol derivatives by NQR, NMR, and emission Mössbauer spectroscopy. The influence of intermolecular, intramolecular, and bifurcated O-H…I and O-H…O bonds on the properties of iodine-carbon bonds is demonstrated. Ionized and non-ionized forms of tyrosine differ by the probability of H-bond formation. The simultaneous use of 127I NQR and emission Mössbauer 125I spectroscopy open the possibility to determine the types of tellurium-organic substances formed in the process of K-decay of 125I.
Powder Spectra of 51V NMR in CuV2S4: Possible Coexistence of Charge and Spin Density Waves
Authors: Nishihara H. , Todo N. , Hagino T. , Nagata S. 
Published: February 2015

Abstract
NMR experiments are reported for the copper chalcogenide spinel CuV2S4 , which has incommensurate lattice distortions at low temperatures in spite of the cubic symmetry at high temperature. A broad spin-echo spectrum of 51V has been observed below 90 K at 17 MHz. but it shows a remarkable frequency dependence where it becomes sharper with decreasing frequency. Possible coexistence of charge and spin density waves is suggested at low temperatures in this material.
Correlation between Structural, Infrared and Nuclear Quadrupole Resonance Data of Iodates
Authors: Petrosyan A.M. , Shishkin V.A. 
Published: February 2015

Abstract
The peculiarities of the structure and the IR and NQR spectra of acid iodates and pyroiodates which contain the I2O5 group are reported. Based in this, the results for several iodates that contain organic cations are considered.
Nuclear Spin-Lattice Relaxation of a Spin System with Strong Heteronuclear Magnetic Interaction
Authors: Furman G. B. , Kunoff E. M. , Goren S. D. 
Published: February 2015

Abstract
Results are presented of a theroretical consideration of the nuclear quadrupole resonance and spin-lattice relaxation for a sample containing nuclei of two different types coupled by strong heteronuclear dipole-dipole interactions and influenced by an external continuous or pulsed ra-diofrequency magnetic field acting only on the nuclei of one sort with spin I > 1/2. A kinetic equation is obtained from which the time dependence of the magnetization of the sample is derived. The kinetic coefficients are calculated as a function of the concentration and distribution of the nuclei of both sorts.
35Cl NQR Study of Thermoactivated Motions of Nitro Groups in Picryl Chloride
Authors: Kyuntsel Igor A. 
Published: February 2015

Abstract
The temperature dependences of the 35Cl NQR frequency (ν), spin-lattice relaxation time (T1), and spin-spin relaxation time (T2) have been studied in 2,4,6-trinitrochlorobenzene (picryl chloride) from 77 K up to the melting point (354 K). The T1(T) curve exhibits a pronounced composite mimimum near 300 K which gives evidence for the reorientations of the two ortho-NO2 groups around their two-fold symmetry axes with the activation energies of 27.4 kJ mol - 1 and 31.2 kJ mol - 1. These values can be related to the ortho-NO2 groups having the twist angles of 33° and 81°, respectively (the crystal structure of picryl chloride is known). The T2(T) dependence exhibits interesting features, too: a deep minimum about 140 K and a new rapid decrease above 270 K.
NQR Investigation of Anion Dynamics in Rb2Zn(Cl1 - xBrx)4
Authors: Subramanian R. K. , Maheswari S. Uma , Venu K. , Sastry V. S. S. 
Published: February 2015

Abstract
The structural stability of Rb2Zn(Cl1 - xBrx)4 (x = 1% and 3%) is investigated using the 35Cl quadrupole resonance frequency and spin lattice relaxation time (T1Q) in the paraelectric (PE) phase. The PE to incommensurate (IC) phase transition temperature T1, observed at 302 K in the pure compound, is lowered to 300 K for x = 1 % and to 293 K for x = 3%. These effects are smaller than in the earlier reported case of 3% Cs substitution in Rb2ZnCl4 , which reduces T1 by 25 K. While bigger cation substitution affects only the barrier for anion dynamics about directions perpendicular to the a-axis (direction of low temperature IC modulation wave), bigger anion substitution is found to affect the barrier for anion dynamics about the a-axis as well. The present study also indicates that the cusp like dip in T1Q observed while approaching T1 from above (characterizing the soft mode condensation associated with the structural phase transition) is essentially unaffected by anion impurity substitution, in contrast to the case where bigger cation substitution tends to smear the transitional effects. These results seem to suggest the dominant role played by cations in stabilizing the PE phase of these A2BX4 systems, in comparison to anions.
35Cl NQR in Solid Trichloroacetyl Halides
Authors: Gordeev A. D. , Osipenko A. N. , Soifer G. B. 
Published: February 2015

Abstract
By 35Cl NQR the temperature dependences of the resonance frequencies and spin-lattice relaxation times for the 35Cl nuclei have been studied in solid CCl3COHal (Hal = F, CI, Br, I). A linear correlation between the average 35Cl NQR frequencies of the CCl3 groups and the electronegativities of the halogen atoms in the COHal groups has been discovered. The temperature-dependent NQR data reveal thermoactivated reorientations of the CCl3COHal molecules as a whole in the crystal lattice. The activation energies of this motion are found to lie in the range 31 - 37 kJ mol - 1
Inter-plane Coupling and Spin Gap -an NMR/NQR Look on Typical Properties of High-Temperature Superconductors
Authors: Brinkmann D. 
Published: February 2015

Abstract
The paper discusses some NQR/NMR studies performed on Y-Ba-Cu-O superconductors at the University of Zürich. In particular, we review studies performed in Y2Ba4Cu7O15 by measuring various planar Cu NQR/NMR parameters: the spin-lattice relaxation time, the Knight shift and the indirect component of the Gaussian contribution to the spin-spin relaxation time. The temperature dependence of these parameters reveals a coupling between adjacent planes of a double plane. The existence of the inter-plane coupling has independently been confirmed by performing NQR Spin-Echo Double Resonance (SEDOR) experiments. The appearance of a spin gap seems to be the consequence of inter-plane coupling.
Ru NMR and NQR Studies in CeRu2
Authors: Ishida K. , Mukuda H. , Kitaoka Y. , Asayama K. , Onuki Y. 
Published: February 2015

Abstract
We have carried out Ru NMR and NQR measurements in superconductor CeRu2 having Tc = 6.1 K in the temperature range of 1.3-30 K. From the 99Ru NMR in 10.2 T above Hc2 , T1T = const was found in the measured-T range, and the value of T1TK2 is almost the same as that in the uncorrelated Korringa relation, suggesting that there does not exist the strong spin fluctuation of Ru d-spins. The property of the superconducting state was investigated by using Ru NQR. We observed the Hebel-Slichter peak just below T c and the exponential decrease in 1/T1 indicating that this superconductivity has an ordinary s-wave character. The effect of Al substitution for Ru was also studied by NMR and NQR.
On the Shock Front Thickness in Water and other Molecular Liquids
Authors: Hess Siegfried 
Published: February 2015

Abstract
Theoretical explanations are presented for the deviation of the shock front thickness from linear hydrodynamics, as observed by W. Eisenmenger (1964) in water and several molecular liquids for large driving pressure differences. Two mechanisms are proposed, which are based on generalizations of the Maxwell relaxation equation for the friction pressure tensor. One is due to the spatial inhomogeneity and linked with piezo-electric or piezo-tetradic effects. The other is caused by nonlinearities which account for shear thickening.
Structure of Ni-P Melts by X-Ray Diffraction
Authors: Sedelmeyer B. , Steeb S. 
Published: February 2015

Abstract
X-ray diffraction was done with molten Ni81 P19 (930°C) and with molten Ni68.8 P31.2 (1160°C). The second peak of the structure factor and the pair correlation function of the Ni81P19 -melt shows a shoulder, as was observed for amorphous Ni80P20 . The first two peaks in the pair correlation function can be modelled using crystalline Ni3 P besides molten Ni. In the case of Ni68.8P31.2 , the first peak in the pair correlation function was modelled using the distance and coordination number as in crystalline Ni2P.
Temperature Effect on the Absorption and Fluorescence Spectra of p-Cyano-N,N-dimethylaniline in Dichloroethane and Ethyl Acetate
Authors: Kawski A. , Piszczek G. 
Published: February 2015

Abstract
The effect of temperature (293 ÷ 413 K) upon absorption and fluorescence spectra of p-cyano-N,N-dimethylaniline (CDMA) was investigated in 1,2-dichloroethane and ethyl acetate. Two fluorescence bands, a and b, were already observed at 293 K, with the intensity of band b increasing strongly with temperature in both solvents. The absorption and fluorescence b bands of CDMA were found to be independent of the orientation interaction with the solvent. On the other hand, the longwave band of fluorescence a undergoes a strong hypsochromic shift resulting from the decrease in the permittivity with increasing temperature. Based on these observations, the electric dipole moment μe in the 1Lb state (shortwave band of fluorescence b) was found to be equal to the dipole moment,μg, in the ground state. The electric dipole moment μe in the 1La state (the longwave band of fluorescence a), which is strongly stabilized by the polar solvent, is about 2.5 times as high as μg , amounting to 54 x 10- 0 Cm (16.2 D) for μg = 22.5 x 10 -30 Cm (= 6.75 D).
Notiz: The Microwave Spectrum of the Benzonitrile-Water Complex
Authors: Storm V. , Consalvo D. , Dreizler H. 
Published: February 2015

Abstract
We report on the measurement and assignment of the benzonitrile-water complex rotational spectrum in the vi-bronic ground state. This study was facilitated by a newly constructed low frequency molecular beam Fourier trans-form microwave spectrometer.
Notiz: A Symbolic Computation-Based Method and Two Nonlinear Evolution Equations for Water Waves
Authors: Gao Yi-Tian , Tian Bo 
Published: February 2015

Abstract
A symbolic-computation-based method, which has been newly proposed, is considered for a (2+1)-dimensional generalization of shallow water wave equations and a coupled set of the (2 +1)-dimensional integrable dispersive long wave equations. New sets of soliton-like solutions are constructed, along with solitary waves.
ab initio Calculation of 33S Quadrupole Coupling Constants. Reanalysis of the 33S Hyperfine Structure in the Rotational Spectrum of Thiirane
Authors: Kirchner Barbara , Huber Hanspeter , Steinebrunner Gerold , Dreizler Helmut , Grabow Jens-Uwe , Merke Ilona 
Published: February 2015

Abstract
We present quantum chemical calculations on the MP4(SDQ) level with basis sets of high local quality to determine the nuclear quadrupole coupling tensor of 33S in a series of molecules, which were investigated up to now by microwave spectroscopy. The analysis of the nuclear quadrupole coupling in the rotational spectra provided experimental information on the tensors. As an example for such an analysis, improved values for thiirane, C2H4
33S, are given: χaa = - 32.9425(78) MHz, χbb = -16.402(14) MHz, χcc = 49.345(14) MHz.
Anisotropie Interaction Potentials for He-Pyrrole, He-Furane and He-Thiophene from total Differential Cross Section Measurements
Authors: Schmidt Ralf , Gebauer Christian , Klein Olaf , Seidel Wolfhart 
Published: February 2015

Abstract
Differential cross section measurements are reported for scattering of an improved He-atomic beam by crossed beams of Pyrrole, Furane and Thiophene. The damping of the DCS diffraction oscillations is used to extract reliable anisotropic intermolecular potentials, applying the infinite order sudden approximation (IOSA).
EPR of Gd3+ in Sulfate Host Crystals of Low Symmetry
Authors: Bode M. , Mosel B. D. , Müller-Warmuth W. 
Published: February 2015

Abstract
Electron paramagnetic resonance (EPR) spectra of trivalent gadolinium have been investigated in orthorhombic sulfate host crystals MeSO4 with Me = Sr, Ba, Cd, Hg, Pb and K2SO4 . Because of the low symmetry of the host crystals and the spin quantum number 7/2, complex spectra for several orientations of the magnetic field containing a large number of individual lines had to be analyzed. The spin Hamiltonian parameters have been rigorously determined from the rotational diagrams. Gd3+ has been found to substitute, first of all, for the monoclinic sites of the host metal ion with charge compensation at larger distances. To a small extent, charge compensation in the vicinity has also been observed, arising from additional centres and spectra with lower intensities. Correlations between EPR spectra and crystal structure are reflected in the values of the zero field splitting parameters.
A New Nuclear-Quadrupole Double-Resonance Technique based on Solid Effect
Authors: Seliger J. , Žagar V. 
Published: February 2015

Abstract
A new nuclear-quadrupole double-resonance technique is described. It has a higher sensitivity and a higher resolution than the conventional nuclear-quadrupole double-resonance technique based on solid effect. The new technique involves magnetic field cycling between a high and a low static magnetic field and simultaneous application of two rf magnetic fields when the sample is in the low static magnetic field. A strong rf magnetic field induces "forbidden" simultaneous transitions in a magnetic (usually 1H) and in a quadrupole spin system and thus couples the two spin systems. A weak rf magnetic field induces transitions between the energy levels of the quadrupole nuclei and simulates a fast spin-lattice relaxation of the quadrupole nuclei when its frequency matches an NQR frequency. The sensitivity and resolution of the new technique are discussed and test measurements in tris-sarcosine calcium chloride are presented.
Thermodynamics of ß-cyclodextrine/water Interactions
Authors: Margheritis C. , Marini A. , Sinistri C. 
Published: February 2015

Abstract
From a purely enthalpic standpoint, the ß-CD hydration, as studied by semiempirical calculations, appears improbable, in contrast to experiment. For the spontaneous hydration process, a compensation mechanism, connected with substrate stabilization and/or entropy increase, is suggested on the basis of simple thermodynamic considerations. The analysis is done on the basis of a single parameter Ew (> 0), which represents the energy needed to transfer a mole of water from the liquid to the ß-CD absorbed phase.
The model, although simple, allows predictions largely consistent with the experimental results, while suggesting possible interpretations.
Thermochemical Nonequilibrium in Rapidly Expanding Flows of High-Temperature Air
Authors: Nishida Michio , Matsumotob Masashi 
Published: February 2015

Abstract
• This paper describes a computational study of the thermal and chemical nonequilibrium occuring in a rapidly expanding flow of high-temperature air transported as a free jet from an orifice into low-density stationary air. Translational, rotational, vibrational and electron temperatures are treated separately, and in particular the vibrational temperatures are individually treated; a multi-vibrational temperature model is adopted. The governing equations are axisymmetric Navier-Stokes equations coupled with species vibrational energy, electron energy and species mass conservation equations. These equations are numerically solved, using the second order upwind TVD scheme of the Harten-Yee type. The calculations were carried out for two different orifice temperatures and also two different orifice diameters to investigate the effects of such parameters on the structure of a nonequilibrium free jet.
Notiz: Modification of the Generalized tanh Method with sech Function for Generalized Hamiltonian Equations
Authors: Tian Bo , Zhao KeYi , Gao Yi-Tian 
Published: February 2015

Abstract
We modify the generalized tanh method with the sech function, so as to obtain a new class of the soliton-like solutions to a coupled set of generalized Hamiltonian equations.
Das Teilchen im Kasten: Strukturen in der Wahrscheinlichkeitsdichte / The Particle in a Box : Structures in the Probability
Authors: Stifter P. , Leichtie C. , Schleich W. P. , Marklof J. 
Published: February 2015

Abstract
Recently W. Kinzel found characteristic structures, e. g. canals and ridges, in the contour plot of the quantum probability density of a particle moving in a box with infinitely high walls. Using the Wigner function we provide an analytical explanation of this numerical observation. Moreover we demonstrate that similar space-time structures also appear in other potentials, such as the one governing the vibrational motion of a diatomic molecule.
Fingerprints of Superpositions of Multifractals and Second Order Phase Transitions
Authors: Stoop Ruedi 
Published: February 2015

Abstract
The generic model of superimposed multifractal measures is discussed from the generalized entropy point of view. Natural conditions for the existence of second order critical lines are given. The second order phase transitions may manifest themselves in stopping points of the entropy-like thermodynamic functions. The findings are of experimental relevance.
Is the Uncertainty Relation at the Root of all Mutual Exclusiveness?
Authors: Sen D. , Basu A. N. , Sengupta S. 
Published: February 2015

Abstract
It is argued that two distinct types of complementarity are implied in Bohr's complementarity principle. While in the case of complementary variables it is the quantum mechanical uncertainty relation which is at work, the collapse hypothesis ensures this exclusiveness in the so-called wave-particle complementarity experiments. In particular it is shown that the conventional analysis of the double slit experiment which invokes the uncertainty principle to explain the absence of the simultaneous knowledge of the which-slit information and the interference pattern is incorrect and implies consequences that are quantum mechanically inconsistent.
Absorption, Fluorescence and Emission Anisotropy Spectra of 4-Cyano-N,N-dimethylaniline in Different Media and at Different Temperatures
Authors: Kawski A. , Piszczek G. 
Published: February 2015

Abstract
The effect of temperature on fluorescence and emission anisotropy spectra of 4-cyano-N,N-dimethylaniline (CDMA) was investigated in viscous (glycerol and paraffin oil) and rigid (polyvinyl alcohol) PVA and polyvinyl chloride) PVC) media. A strong effect of temperature on the intensity of a and b emission bands was observed. It was also found that the emission anisotropy, r, does not vary in the longwave emission band a at a fixed temperature but decreases in the emission band b together with the decreasing wavelength. The latter effect is due to the fact that the transition moment in this band is perpendicular to the long axis of the CDMA molecule. For CDMA in paraffin oil, a normal b band with negative emission anisotropy only occurs. In all other media used, the emission anisotropy has lower values, approaching zero, which results from the considerable covering of band b with a broad emission band a.