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Refractive index data have been obtained between 5000 and 20 cm −1 for chloroform, bromoform and their deuterated derivatives. These dispersion data have been analyzed to yield infrared band intensities and atomic polarizations.

A method is presented of measuring the uniaxial anisotropy field Hk and coercive force Hc by forced vibrations of the magnetization vector Ms in two mutually perpendicular fields lying in the film plane, one of which, of low intensity, varies sinusoidally. The vibration amplitude of Ms exhibits maxima as a function of the dc field from which positions Hk or Hc can be determined according to the case whether the easy axis is directed perpendicular or parallel to the dc field. Theoretical predictions are confirmed experimentally using the planar galvanomagnetic effect for measuring the Ms vector amplitude. The influence of the amplitude of an ac field on the positions of the maxima is discussed. Es wird eine Methode fur die Messung des uniaxialen Anisotropiefeldes Hk und der Koerzitivkraft Hc durch erzwungene Schwingungen des Magnetisierungsvektors Ms in zwei zueinander senkrechten in der Schichtebene liegenden Feldern, von denen eins sich mit niedriger Intensitat sinusformig andert, angegeben. Die Schwingungsamplitude von Ms zeigt in Abhangigkeit vom Gleichfeld Maxima, aus deren Lage Hk oder Hc bestimmt werden kann, in Ubereinstimmung damit, ob die leichte Achse senkrecht oder parallel zum Gleich-feld gerichtet ist. Theoretische Vorhersagen werden experimentell durch Messung der Amplitude des Ms-Vektors mittels des ebenen galvanomagnetischen Effekts bestatigt. Der Einflus der Amplitude des Wechselfeldes auf die Lage der Maxima wird diskutiert.

Dielectric titrations were performed to establish the composition of complexes formed between bases with X–O groups (X = N, S, or P) and some carboxylic acids, and phenols. In all cases the stoichiometric ratio 1 : 1 was found. The dipole moments of the adducts were estimated and the Δµ values, i.e., the increase of the dipole moment due to hydrogen bonding was deduced for various mutual orientations of the interacting components.

Assuming a simple coherent rotation of the magnetization vector, formulas are proposed for the galvanomagnetic voltages parallel and perpendicular to the current as a function of the external magnetic field at various orientations of the easy axis. The theoretical discussion suggests several methods of measuring Hk, one of which is verified experimentally. Unter der Annahme einer einfachen koharenten Rotation des Magnetisierungsvektors werden Ausdrucke fur die galvanomagnetischen Spannungen paralle und senkrecht zum Strom als Funktion des auseren magnetischen Feldes bei verschiedenen Orientierungen der leichten Achse vorgeschlagen. Eine theoretische Diskussion weist auf einige Methoden zur Messung von Hk hin, von denen eine experimentell verifiziert wird.

Thin films containing the Mn5Ge3 intermetallic compound were obtained by a vacuum evaporation technique. The samples were divided into two groups. Films containing up to 60% Mn5Ge3 belong to the first, those containing about 100% belong to the second group. The temperature dependence of magnetization has been measured, and appeared to be similar to those of bulk material, except for a small decrease in the Curie point. The perpendicular-to-surface anisotropy has been measured for group-I films. Its constant depends strongly on temperature and changes from positive values at low temperatures to negative ones at temperatures near the Curie point. Dunne Schichten der intermetallischen Verbindung Mn5Ge3 wurden mit einer Aufdampfmethode im Vakuum erhalten. Die Proben wurden in zwei Gruppen eingeteilt. Schichten bis zu 60% Mn5Ge3 gehoren zur ersten, solche mit etwa 100% zur zweiten Gruppe. Die Temperaturabhangigkeit der Magnetisierung wurde gemessen; sie scheint derjenigen von Volumenmaterial ahnlich zu sein, mit Ausnahme eines kleinen Abfalls am Curiepunkt. Die Anisotropie senkrecht zur Oberflache wurde fur Schichten der Gruppe I gemessen. Die Konstante hangt stark von der Temperatur ab und andert sich von positiven Werten bei niedrigen Temperaturen zu negativen Werten bei Temperaturen in der Nahe des Curiepunktes.

Magnetostriction of thin Ni-films is investigated by the multibeam interference method. The magnetostriction constant λs is calculated from the changes in the mica substrate's deflection as it yields to the stresses in the films. Its value does not differ appreciably from that of bulk nickel. The deflections of the mica substrate due to the stresses stemming from the evaporation process are apparent in the interference pattern as a system of hyperbolas. This can be explained as originating in a saddle-like deflection of the substrate.

The hydrogen-bonded complex between nitric acid and ammonia molecules has been studied by the ab initio molecular orbital method using the 4-31G basis set. The calculated interaction energy for the complex (ΔE = −91.4 kJ mole−1) indicates that one is dealing with the strongest “nonionic” H-bonded complex considered hitherto by theoretical methods. Other properties of the hydrogen-bonded complex such as geometrical parameters, dipole moment, amount of charge transfer, and stretching force constants of the OH and (OH)… N bonds are calculated and discussed.

The photoacoustic (PA) spectra of rare earth pentaphosphates of the general formula REP5O14, where RE = Pr, Nd, Ho, Er, Tm, are reported. The photoacoustic bands were identified and compared with the absorption spectra. For quantitative analysis of PA bands of lanthanide (III) ions, the intensity ratio vector is introduced, characterizing the intensity distribution of f-f transitions. It was found that the relative intensities of photoacoustic bands are comparable with the intensities of absorption bands. It is concluded that the nonradiative relaxation mechanism leading to the PA signal is independent of the manifold-to-manifold J-J' radiationless transitions.

CNDO based molecular orbital calculations are reported for the HCl crystals in the orthorhombic and cubic lattice forms. The orthorhombic crystals was found to be more stable by about 3.8 kcal/mol. The change in the molecular properties in the gas phase monomer and in crystal is discussed.

The CNDO/S CI method has been employed to study the electronic transitions of the hydrogen malcate ion. Nagakura's hypothesis that the first electronic transition at 211 nm is of charge-transfer type was not confirmed by the results of the calculations. The influence of the hydrogen-bonded proton on the electronic spectra is also discussed.

Semi-empirical and ab initio calculations on 1:1 NH3lithium halide complexes show that the lithium bond is stronger than the hydrogen bonds formed by the corresponding hydrogen halides. There is an elongation of the Li-halogen bond and a decrease in the stretching force constant in the complex. Unlike in hydrogen bonds, there is an increase in charge on the bridging atom in lithium bonds.

A study of the influence of uniaxial stresses on the planar galvanomagnetic effect in thin Ni-Fe-Mo films evaporated in vacuum has been performed. Galvanomagnetic voltage was measured at different value of stress and applied field, rotated in the plane of the sample. Magnetoelastic hysteresis depending on the applied field was found.

Galvanomagnetic effect was used for studying the magnetization reversal processes in thin NiFe-NiFeMn films with the unidirectional anisotropy. The experimental results were compared with the simple coherent magnetization rotation model. A large contribution of rotation of the magnetization vectorM s to the reversal process in easy direction was found (around 22°). The dependence of angular dispersionα45 on external fieldH‖ was also measured.

Die statistische Auswertung der Daten von 608 Harnsteinpatienten, die im Rahmen der retrospektiven Studie des von der DFG unterstutzten Aachener Harnsteinregisters erfolgte, zeigte, das von den bekannten lithogenen Faktoren lediglich die Calcium-ausscheidung im Urin einen signifikanten Einflus auf die Anzahl der Harnsteinerkrankungen und die Rezidivintervalle hatte. Dies belegt die Annahme, das zumindest die Genese des Calciumoxalatsteines komplexer Natur ist und nicht durch eine einzige Stoffwechselstorung erklarbar ist.

The basic components of a data- and methodbase system useful for both individual diagnosis and (group-study) research in neuropsychology are described. Such a system enables one to organize, access and evaluate large data-sets of behavioural, neuroradiological and neurological information. The most important component of the system, the data- and methodbase management system, is described in some detail. It operates on databases comprised of Aachen Aphasia Test examinations and standardized CT evaluations as well as on methodbases containing various sets of analysis routines for the psychometric evaluation of (individual) aphasia test results and the evaluation and (graphical) presentation of standardized (individual) CT lesions. Although exemplified for AAT scores the techniques and principles employed are applicable to data- and methodbase systems in general.

This atlas is the first one in the field of vibrational spectroscopy of polyatomic molecules. It is divided into two paragraphs. The first deals with the theory of vibrational spectroscopy in a concise form and considers the most important spectroscopical parameters - frequencies, bandshape and intensities. The second paragraph is dedicated to the infrared (2000-400 cm-1), far infrared (400-40 cm-1) and Raman (2000-10 cm-1) spectra of about hundred different mesomorphic materials with various molecular structure. The polarized IR spectra of the most important liquid crystals is also included. In the second paragraph the assignment of the IR bands to the corresponding intramolecular vibrations is also reported. Almost all spectra is registrated and analysed for the first time. The major important features are: 1. Registration and analysis (for the first time) of vibrational spectra of polyatomic molecules with mesomorphic phases; 2. Registration (for the first time) of vibrational spectra of polyatomic molecules with mesomorphic phase in polarized IR light. Polarized vibrational spectra are very important for clarification of the molecular structure; 3. Assignment (for the first time) of the IR bands of the most important liquid crystalline materials to the corresponding vibrations.

The preliminary results of IR studies on the hydrogen-bonded acid-base complexes and the general discussion of the splitting of the OH vibration band into four components, due to tunneling effect, have been presented.

As a continuation of our investigation of FINEMET alloy thin films, Fe 73.5 Cu 1 Nb 3 Si 13.5 B 9 , with Nb replaced by other high-melting metals W, Mo, Ta, V [1,5], in this work we report studies on the alloys in which these refractory elements were replaced by the following representatives of lanthanides: Yb, Ho, Tb, Gd, Sm, Nd, Pr and Y as an element without a magnetic moment [9]. Their structure was determined on the basis of electron diffraction studies and TEM observations. The structure of as-deposited films was found to be strongly dependent on the deposition conditions. The films deposited for less than 30 seconds were amorphous whereas those deposited for a longer time revealed microcrystallin structure (the temperature of the evaporation source was the same for all samples). The coercive field H c in the film plane and the Hall extraordinary coefficient R 1 together with the value of magnetic saturation induction E g for the films of both types were determined from the magnetooptical Faraday effect and the Hall effect, respectively. A strong correlation between the magnetic behaviour and structural changes of the films was found, i.e., a strong increase in H c and decrease in R 1 with increasing annealing temperature wereobserved.

The aim of this paper is to examine the influence of the ‘inert’ solvent as C 2 Cl 4 and ‘active’ solvent as CH 3 CN on the relaxation time of pyrrole. On the basis of the line-shape analysis imido protons (scalar relaxation of the second kind) relaxation and correlation times of pyrrole in the mentioned solvents have been calculated. The dependence of the line-shape on solute concentration and temperature was studied and the activation parameters for molecular reorientation of pyrrole determined.