bluuebunny/crossref_metadata_2025_split huggingface dataset:
Dissociation Lifetimes of Molecular Ions Produced by Charge Exchange
Authors: Andlauer B. , Ottinger Ch. 
Published: February 2015

Abstract
Ions of the benzonitrile, benzene and thiophene molecules were produced in well-defined states of excitation by charge exchange with Xe+, Kr+, Ar+, CO+, and N2
+. Their subsequent unimolecular decomposition was followed, as a function of time, by allowing the dissociations to take place within a strong homogeneous draw-out field and measuring the kinetic energy of the product ions. The decompositions were found to be purely exponential within experimental error, and the corresponding decay rate constants k (for 2 · 105 sec-1 ≦ k ≦ 5 · 108 sec-1) proved to be monotonically increasing functions of the excitation energy. These are the first unambiguous measurements of this function k(E) for any molecule. In the case of benzene, the reactions C6H6
+ → C6H5
+ + H and C6H8
+ → C4H4
+ + C2H2 were found to be definitely not in competition with one another. Furthermore the dependence of the excitation energy on the impact energy was measured. A variation of the impact energy between 10 and 200 eVc.m. only changes the internal energy E by about 0.1 eV. This value appears to be in qualitative agreement with calculations on near-resonant charge transfer by Gurnee and Magee.
Dynamical Interaction of Electron Waves in a Perfect Single Crystal
Authors: Lehmpfuhl G 
Published: February 2015

Abstract
Electron diffraction from a perfect single crystal shows the influence of many-beam interaction. Investigations with a single crystal wedge allow a direct analysis of the Bloch-waves which are dis-played into their partial waves. The strength of the dynamical interactions in a MgO crystal wedge was investigated by comparing the photographic record of a section through the dispersion surface with many-beam calculations. For a direction of the incident beam near the [110] zone axis the interaction of at least 50 beams has to be taken into account. Using a 50-beam calculation the structure potential V111 was determined to 1.80 volts ±3%.
The influence of many-beam interactions on the absorption and the extinction fringe profiles in electron micrographs is discussed. Analysis of extinction fringes on the basis of a 50-beam approximation allowed the determination of the mean absorbing potential V0
im of MgO to 0.7 volts ±10%.
Der Einfluß des Entladungsgefäßes auf die Bestimmung der Plasmaelektronendichte mit Hohlraumresonatoren / The Influence of the Discharge Tube on the Determination of the Plasma Electron Density by Means of Cavity Resonators
Authors: Janzen G 
Published: February 2015

Abstract
The eigenvalue equation of a plasma-discharge tube configuration in a cylindrical microwave cavity is derived and solved numerically by an exact theory for TMlm0 , TM0mn, and TE0mn resonance modes. The radial and axial electron density profiles are assumed to be homogeneous.
The factors of proportionality between electron density and shift of the resonance frequency derived from the linear perturbation theory are compared with the exactly computed eigenvalues. Hence the range of validity of the linearly computed factors of proportionality (geometry factors) can be established.
By considering the influence of the discharge tube the geometry factors are altered and consequently the sensitivity of the measurement. The influence of the discharge tube can be taken into account by means of suitable correction factors.
Quasi-Equilibrium Theory of Ionic Fragmentation: Further Considerations
Authors: Klots Cornelius E. 
Published: February 2015

Abstract
A recent reformulation of quasi-equilibrium theory is extended to several additional classes of ionic decompositions. Formulae for calculating average translational and rotational energies of the fragments are presented, and kinematic corrections to the formulas are introduced. Illustrative calculations are compared with experiment, and the interesting possibility of maxima in rate constants is noted.
Level-Crossing-Experimente am bewegten Leuchten / Level-Crossing Experiments on High Velocity Atoms
Authors: Bachmann W. , Janke W. 
Published: February 2015

Abstract
Durch Stoßwechselwirkung zwischen einem Helium-Ion und einem Neon-Atom findet unter ande-rem ein Elektroneneinfang in einen angeregten, teilweise ausgerichteten Heliumzustand statt. Es wurde die Breite des durch Elektroneneinfang angeregten 41D-Heliumzustands in Abhängigkeit vom Fremdgasdruck des Neon und in Abhängigkeit von der Geschwindigkeit der Heliumatome mit Hilfe des Hanle-Effekts gemessen. Daraus wurde die Geschwindigkeitsabhängigkeit der Wirkungs-querschnitte σD
(2)(ν) zur Zerstörung der Ausrichtung der angeregten Heliumatome infolge von Stößen mit Neonatomen bestimmt. Im Energiebereich von 5 keV bis 30 keV war das Produkt ν · σD
(2)(ν) konstant, d.h. ν · σD
(2)(ν) proportional ν-1 .
Als zusätzliches Ergebnis erhielten wir die natürliche Lebensdauer des 41D-Zustandes zu (38,4 ± 2,1) nsec.
A Simple and Reliable Dye Laser System for Spectroscopic Investigations
Authors: Kühl J. , Marowksy G. , Kunstmann P. , Schmidt W. 
Published: February 2015

Abstract
Efficient spectral narrowing and accurately reproducible tuning of a dye laser has been achieved by the combination of a low-loss narrow-band interference filter and a solid-quartz-plate-Fabry-Perot-etalon. Bandwidths as small as 5-10-3 Å were obtained by this simple system increasing the spectral density by a factor of at least 2 · 103.
Photolyse des Äthylens im Bereich 147 — 193 nm / Ethylene Photolysis At 147 — 193
Authors: Potzinger P. , Glasgow L. , Bünau G. 
Published: February 2015

Abstract
Ethylene photolysis was investigated at 147, 163, 185 and 193 nm. The following three primary processes were observed at all wavelengths
C2H4 + hν → C2H2 + H2, (1)
C2H4 + hν → C2H2 + 2H, (2)
C2H4 + hν → C2H3 + H. (3)
(1) was independent of all experimental parameters tested: temperature, pressure, wavelength, scavenger, and light intensity. (2) decreases with increasing pressure and increases with increasing photon energy. (3) shows almost no pressure dependence at 185 nm and decreases in importance with increasing photon energy. A kinetic analysis shows that participation of at least three different states of ethylene must be invoked to explain the results. A tentative correlation of these states with the spectroscopic states of ethylene is given.
Quantenchemische und spektroskopische Untersuchungen an Porphyrinen. III. Die Chlorine / Quantum Chemical and Spectroscopical Studies on Porphyrins. III. The Chlorins
Authors: Knop J.V. , Stichtenoth H. 
Published: February 2015

Abstract
Zur Deutung der Elektronenanregungsspektren von Chlorin, Ni-Chlorin e6 , des Chlorin-Dianions und Chlorin-Dikations wurden Pariser-Parr-Pople-Berechnungen mit Berücksichtigung von 90 ein-fach angeregten Konfigurationen durchgeführt.
Neben neuen Gesichtspunkten zur Zuordnung der Elektronenübergänge im Absorptionsspektrum konnten auch experimentelle Voraussagen hinsichtlich der Ladungsverteilung im Molekülgerüst bestätigt werden.
Zur Begrenzung der radial en Ausdehnung des Li chtbogenstromes durch ein axiales Magnetfeld. II. Skalengesetze und Vergleich mit Experimenten / On Limitation of the Radial Extent of the Arc Current by Means of an Axial Magnetic Field. II. Scaling Laws and Comparison with Experimental Results
Authors: Klüber O. 
Published: February 2015

Abstract
In an arc with superimposed axial magnetic field, radial current components cause a rotational motion of the plasma column and produce azimuthal Hall currents and hence electromotive forces such that the arc current is guided by the magnetic field lines. In the first part of this paper the steady-state plasma equations have been solved for a homogeneous plasma in simple geometry, allowance being made for finite viscosity. Here, scaling laws giving the radial extent of the arc current are obtained. In addition, electrodes with finite cross sections are treated. The results of model calculations agree well with experimental data. Generally, the model is applicable, if the angular frequency of the plasma is small compared with the ion gyration frequency.
Molecular Force Fields of Tungsten and Uranium Hexachlorides
Authors: Avasthi M.N. , Mehta M.L. 
Published: February 2015

Abstract
Molecular force field studies of tungsten and uranium hexa-chloride have been carried out using the Urey-Bradley force field (UBFF) and the orbital valence force field (OVFF). Weighted least square adjustment has been used to fit the observed frequencies. Comments are also made on the suit-ability of the force fields used. The trends in stretching force constants have been discussed.
Time Correlation Functions for Gases of Linear Molecules in a Magnetic Field
Authors: Pierre A. G. St. , Köhler W. E. , Hess S. 
Published: February 2015

Abstract
Time correlation functions for gases of linear molecules in a static homogeneous magnetic field are derived from the set of transport relaxation equations obtained from the linearized Waldmann-Snider equation. In particular, the complex auto-and cross correlation functions of the friction pressure tensor and the tensor polarization are considered. They are of importance for the viscosity, the depolarized Rayleigh spectrum, and flow birefringence. For the gases HD and CO2 their real and imaginary parts are plotted as functions of a reduced time and discussed. Lastly, the influence of a constant magnetic field on the flow birefringence property of a gas of linear molecules in a Couette flow arrangement is treated. The principal axes of the dielectric tensor are rotated about the field direction. For two field orientations the respective angles of rotation are determined. The eigenvalues of the dielectric tensor reveal the tendency of the optical and transport properties of the gas to decouple for increasing field strengths
Frequenzverschiebungen durch CD3 -Substitution in den Schwingungsspektren von Trimethylchlorsilan, Hexamethyldisiloxan und Trimethoxysilan und ihre Verwendung zur Kraftkonstantenberechnung
Authors: Höfler Friedrich 
Published: February 2015

Abstract
Die Untersuchung der IR-und Raman-Spektren von (CD3)3SiCl und (CD3)3SiOSi (CD3)3 führt zu einer Neuzuordnung der ρCH3-Schwingungen in Trimethylsilylverbindungen. In Normalkoordina-tenanalysen an diesen Verbindungen sowie an HSi (OCH3)3/HSi (OCD3)3, die sich auf die gemes-senen Isotopenverschiebungen stützen, wird das Schwingungsverhalten der Methylgruppen durch die Einbeziehung von ρCH3 (CD3)-Koordinaten angemessener wiedergegeben als durch eine Betrachtung als Punktmassen. Für die vornehmlich interessierenden Valenzkraftkonstanten ergeben sich folgende verbesserte Werte: f(SiCl) 2,84; f(SiO) 4,60 (Hexamethyldisiloxan) bzw. 5,13 mdyn/Å (Tri-methoxysilan) und f(SiC) 2,84-2,89 mdyn/Å
Genäherte natürliche Orbitale für die Grundzustände von Li und Li-; Elektronenaffinität von Li- / Approximate natural orbitals for the groundstates of li and li-; electron-affinity of li-
Authors: Grün Norbert 
Published: February 2015

Abstract
Starting from a set of Slater-type atomic orbitals with seven s-, four p-, one d- and one f-type functions the total wavefunction is constructed by a C I-calculation. The highest degree of the secular equation is 84 for Li (2S) and 142 for Li- (1S). By diagonalizing the first-order density matrices approximate natural orbitals are obtained. These are analysed and used again in a further C I-calculation. The best values for the electron-affinity are 0.572 eV and 0.614 eV. For the latter value only the correlaton energy of the L-shell of Li- is considered
Der Einfluß der Restwechselwirkung VPN auf das Rotationsspektrum des u-u-Kerns 166Ho / The influence of the residual interaction fpu on the rotational spectrum of the odd-odd nucleus 166ho
Authors: Reinecke M , Ruder H , Volz H 
Published: February 2015

Abstract
Starting with a model for odd-odd nuclei, which had been used in former investigation (rigid, symmetrical top for the deformed even-even core, two extra particles in a Nilsson potential), the influence of the coupling term Hc and of the residual interaction VPN on the rotational spectrum of the odd-odd nucleus 166Ho are discussed. It is shown, that in this nucleus neither the coupling term Hc nor a pure Wigner force can explain the characteristic features of the rotational spectrum. It is therefore necessary to introduce a residual interaction VPN, which contains at least a spin-spin term. The explicit calculation for the nucleus 166Ho with a simple ansatz (δ-interaction with spin-spin term) already leads to a qualitative explanation of the particularities in the observed rotational spectrum. The investigations show a way how to get more information about the protonneutron interaction in odd-odd nuclei
On the Exchange Part of the Single-Particle Spin-Orbit Potential Following from the Nucleon-Nucleon Spin-Orbit Interaction
Authors: Penzel R , Stocker W 
Published: February 2015

Abstract
The exchange part of the single-particle spin-orbit potential following from a two-body spin-orbit potential is calculated. Scheerbaum's approximation of setting the exchange part equal to the direct part is investigated
Amplituden für kohärente Neutronen-Streuung gemessen an chemischen Verbindungen / Coherent Neutron Scattering Amplitudes Obtained from Chemical Compounds
Authors: Koester L. , Knopf K. 
Published: February 2015

Abstract
Coherent Neutron Scattering Amplitudes Obtained from Chemical Compounds Utilizing the small angle scattering of slow neutrons by Christiansen-filters we could determine with a good accuracy the scattering amplitudes of powders by comparing with wellknown liquids. Investigations on powders of halides and sulfates yielded coherent scattering amplitudes of the bound atoms (in 10-13 cm) :
a (Na) = 3.63 ±0.02; a(K) =3.71 ±0.02;
a (Rb) =7.08 ± 0.02; a (Cs) = 5.42 ± 0.02;
a(Tl) =8.89 ±0.02; a (Br) =6.77 ±0.02;
and a (I) =5.28 ±0.02.
The scattering amplitudes of the liquids and the elements as standards are based on directly determined amplitudes from gravity-mirror measurements.
Zur Theorie der Jordan-Nachwirkung / Theory of Thermally Activated Relaxation in Ferromagnets
Authors: Hahn Artur 
Published: February 2015

Abstract
Theory of Thermally Activated Relaxation in Ferromagnets The theory of the thermally activated relaxation process in a ferromagnet, leading to the phenomenon of Jordan-type aftereffect, is reinvestigated. The analysis is based on a more general statistical approach than the concept of a macroscopic free energy as a function of a macroscopic state variable usually employed in this field. Within the simplest possible model analytical results are obtained, leading to a re-establishment of the usual concept for small systems and its break-down for systems larger than a critical size. For large systems asymptotic results are obtained differing qualitatively from those of the conventional scheme. The most important result is a temperature-independent viscosity coefficient 5V , defined by Eq. (3) of the text.
A Phenomenological Study of the Steady-State Current Sheet Speed in a Magnetically Driven Shock Tube
Authors: Chang C. T. 
Published: February 2015

Abstract
The discrepancy between the measured steady-state speed of the current sheet and the theoretically predicted value is examined through a detailed analytical and experimental study of the basic assumptions used in the model. It is found phenomenologicaly that the observed deviation at dis-charge conditions of low voltage and high pressure could be attributed mainly to the spreading of the current-carrying region in time. The deviation occurring at discharge conditions of high voltage and low pressure could be attributed to the possible presence of an ion drag caused by the interaction between the plasma and the electrode surface.
Zur Geschwindigkeit der Ausrichtung nematischer Flüssigkeiten durch Magnetfelder / Kinetics Of Alignment Of A Nematic Liquid Crystal In Magnetic Fields /
Authors: Heppke G. , Schneider F. 
Published: February 2015

Abstract
The rotation of the molecules in a nematic liquid crystal is studied after rotating the axis of the aligning magnetic field. The process of realignment is observed by doping the liquid crystal with an electrolyte and measuring the cross voltage U* which is induced perpendicular to the applied electric field. The resulting cross voltages are compared with the stationary values and it can be shown that the degree of order with respect to the rotating director remains almost constant. Therefore, the time dependence of the angle 0 between director and magnetic field can be calculated from the measured cross voltage using the steady state equation U* = U*(Φ) . Φ(t) satisfies the formula
ln | tan Φ | = ln | tan Φ0 | - (χa H2/γ1) t
which is derived from the differential equation for the rotation of the
director. This formula allows the calculation of the viscosity coefficient γ1, giving a value of 1.08 P for MBBA at 25 °C. An activation energy of 11.5 kcal mol -1 is determined from the temperature dependence of the viscosity coefficient.
Über eine Methode zur Bestimmung der Dissoziationsrelaxationszeiten in Kr—Cl2-Gemischen / About A Method To Determine Dissociation Relaxation Times In Kr-Cl2-Mixtures
Authors: Pletsch G. 
Published: February 2015

Abstract
Streak photographs from the emission of shock tube heated Kr-Cl2-mixtures show two regions in the reflected wave with different front velocities and different temperatures. The region near the end plate of the shock tube is assigned to the dissociation relaxation zone of the incident shock, the following to the equilibrium zone. The relaxation times are determined from these photographs in combination with the data of the incident shock.
Einfache lokalisierte Orbitale für die Moleküle CH4, NH3 und H2O / Simple Localized Orbitals For The Molecules CH4, NH3 und H2O
Authors: Krell J. , Zuhrt Ch. , Zülicke L. 
Published: February 2015

Abstract
Results of ab-initio bond-orbital calculations for the molecules CH4, NH3 and H2O are reported. The orthonormal localized orbitals for inner shells, lone pairs and bonds are compared with the corresponding localized SCF orbitals and discussed with respect to their dependence upon the basis functions and the hybridization as well as to their transferability. According to present experience, application of the bond-orbital approach in the theoretical determination of conformational energies is particularly promising.
Hyperfeinstruktur von CsJ / Hyperfine Structure of CsI
Authors: Hoeft J. , Tiemann E. , Törring T. 
Published: February 2015

Abstract
The quadrupole hyperfine structure of 133Cs127I was measured on the rotational transition J = 2 → 3 at 4.2 GHz. The obtained quadrupole coupling constants of 127I in various vibrational states are reported.
Eine SCF-MO-CI-Berechnung des C2 -Moleküls mit einer atomaren Basis von kontrahierten Gauß-Funktionen / An scf-mo-cl calculation of the c2 molecule using an atomic basis of contracted gaussian lobe functions
Authors: Barsuhn J 
Published: February 2015

Abstract
The C2-molecule seems to be a very useful object for the purpose of comparing different quantum chemical calculations because of the extensive experimental data available for this molecule. In the present treatment a basis set consisting of 25 primitive Gaussian lobe functions which have been contracted into 4 s-groups and 2X3 p-groups has been used. SCF orbitals obtained for the ground state configuration 1 πu
4 have been employed in two CI-calculations at R-values in the vicinity of the equilibrium internuclear distance. The calculation involving only virtual a-orbitals agrees qualitatively with the experimental data for the three known Rydberg states. The most extensive Cl-treatment employed overestimates the excitation energies to the higher states by up to 1.7 eV; the relationship between the theoretically calculated transition energies and the corresponding experimental values is approximately linear, however. The results are compared with previous extensive CI-calculations of FOUGERE and NESBET who used two different 2-zeta Slater basis sets
Abschätzung von Zustandsdichten des Silbers in a-Silber-Mischkristallen mit Gallium, Indium, Germanium und Zinn auf Grund thermodynamischer Untersuchungen mittels galvanischer Festkörperzellen / An estimation of densities of state of silver in a-solid solutions of silver with gallium, indium, germanium and tin based on thermodynamic investigations by means of solid state galvanic cells
Authors: Predel B , Schallner U 
Published: February 2015

Abstract
The partial free enthalpies of formation of the binary a-solid solutions of silver with gallium, indium, germanium and tin were determined at 1000 °K from the EMF of suitable solid state galvanic cells. A further evaluation of the results taking into account known enthalpies of for­mation yielded the complete partial and integral excess functions of these solid solutions. An analysis of the difference of the excess values of the partial free enthalpies of formation of the components showed that the lattice distortion, due to differences in atomic radii of the solid solutions studied, is not very significant. Differences in the structure between the solid solution and its components can be clearly noted only in the case of the silver-germanium solid solutions. The energetics of the alloys are determined principally by the filling of the 5s1 conduction band of the silver by the electrons contributed by higher-valent constituents. From the thermodynamic results the density of state of the conduction band of the silver was estimated to be smaller than 0.31 electr. per atom and eV. The density of state increases with increasing concentration of the alloying component; this can be explained by a change in the Fermi surface in the silver host lattice
Mikrowellenspektrum, Rotationskonstanten, Zentrifugalverzerrungskonstanten und Kernquadrupolkopplungskonstanten des CD3SiH2Cl. Über Bindungseigenschaften in Silicium-Halogeniden: 1. Mitteilung / Microwave spectrum, rotational constants, centrifugaldistortion constants and nuclear quadrupole coupling constants of CD3SiH2Cl
Authors: Zeil Werner , Gegenheimer Richard , Pferrer Saskia , Dakkouri Marwan 
Published: February 2015

Abstract
Microwave The microwave spectra of the following isotopic species of methylchloro-silane CD3
28SiH2
35Cl, CD3
29SiH2
35Cl, CD3
30SiH2
35Cl, CD3
28SiH2
37Cl have been measured and analyzed. The rotational constants, centrifugaldistortion constants and nuclear quadrupole coupling constants have been determined. The Si-Cl-distance is 2.049 Å respectively 2.052 Å as calculated by the rs method. The corresponding angles between the siliconchlorine-bond and the inertia-axis a are Θ = 26°53' respectively 26°49'
Zeeman-Effekt im Rotationsspektrum von Perdeuterodimethylsulfid / Rotational zeeman-effect of perdeuterodimethylsulfid
Authors: Hamer E. , Sutter D. H. , Dreizler H. 
Published: February 2015

Abstract
The rotational Zeeman effect of (CH3)2S and (CD3)2S has been observed under high resolution. Earlier measurements of BENSON and FLYGARE 2 on (CH3)2S were supplemented by the recording of two additional transitions. A line shape analysis was used to evaluate the data which led to the determination of the diagonal elements of the g-tensor and of the susceptibility anisotropies [in 10-6 erg/(G2 mole)] :

From the change of the g-values upon deuteration it was possible to determine the sign of the electric dipole moment (negative end at the sulfur atom)
On the Existence of Antiferromagnetism in Hubbard's Approach to the Hubbard Model
Authors: Jelitto Rainer 
Published: February 2015

Abstract
We investigate the possibility of selfconsistent solutions for antiferromagnetism in the Hubbard model in the decoupling of the Greens functions introduced by Hubbard in his first paper. On the base of this approximation Arai has calculated the band splitting for antiferromagnetism, but, as will be shown in this paper, Hubbard's approach fails to yield antiferromagnetism for nearest neighbour hopping in the same way as it does not yield ferromagnetism, and no selfconsistent solutions of the problem beyond the well known paramagnetic solution do exist.