A few formulae have been derived for the contribution of the dipolar broadening to the second moment of the resonance line in pure quadrupole resonance experiment for crystals in which the following conditions are satisfied:
(1) All nuclear spins involved, both resonant and nonresonant, have spin 3/2.
(2) The electric field gradient tensor at all nuclear sites have axial symmetry. For resonant nuclei the gradient of the electric field has the same magnitude but the symmetry axes of the electric field gradient at several nuclear sites in the unit cell have different directions.
(3) As for the nonresonant unclei no restriction has been set the magnitude of the electric field gradient and its directions.
A comparison is made with the line widths for NaClO₃ and NaBrO₃ observed by K\={o}i et al.

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A variational principle for the electron transport in a magnetic field is described, and the principle is applied to the calculation of the transverse effects of cubic metals in the transverse magnetic field by using an approximate trial function. Our method gives exact solution for the spherical energy hand model. For the anisotropic energy band, our method gives an approximate solution which coincides with the exact solution if the energy dependent relaxation time exists. Relations between the transverse galvanomagnetic and thermomagnetic coefficients, which hold for arbitrary scattering mechanism, are derived.

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Paramagnetic resonance absorption was investigated at centimeter wave-length region in single crystals of copper propionate monohydrate Cu(CH₃CH₂COO)₂·H₂O.
The spectrum obtained is not a normal one expected for a ²D state of Cu⁺⁺ ions in crystals but similar to that observed in copper acetate monohydrate Cu(CH₃COO)₂·H₂O and more complicated. This spectrum can be explained by an effective spin Hamiltonian with an equivalent spin value S=1. This may lead us to a conclusion that each of the magnetic complexes in this crystal consists of a pair of copper ions under a strong interaction and may be created from a bimolecular structure, Cu₂(CH₃CH₂COO)₄·2H₂O as in the case of the acetate. The unit cell of this crystal contains six spatially inequivalent pairs, of which three can be derived from the others by a reflection in its ac-plane. Each pair of ions in this crystal is considered to be under a very similar environment, except the direction of the pairs. The rhombicity in its crystalline field is smaller than that of the acetate.

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The temperature dependence of Hall coefficient of five superlattice alloys of Cu₃Pd, CuZn, Ni₃Cr, Au₃Cu and Ag₃Mg was measured to find the effect of order-disorder transformation upon it. At the transition temperature, the Hall coefficient of Cu₃Pd and Ag₃Mg showed a discontinuous change, while the change of Hall coefficient of other three alloys (CuZn, Ni₃Cr, Au₃Cu) are very small. Applying Muto’s theory, the qualitative discussion was made, and it was found that the general features of the temperature dependence of CuZn and Ni₃Cr are well understood by the theory. For Au₃Cu, the result of the experiment is explained by adopting the assumption of Schubert that each Au atom affords more than one electrons into the conduction band. The assumption also explains why the temperature dependence of Hall coefficient of Au₃Cu differs from that of Cu₃Au.
It remains unknown why Hall coefficient of Cu₃Pd takes strong minimum at transition temperature, while the abrupt increase of the Hall coefficient with the decreasing temperature below T_c can be explained by the existence of a superzone in the ordered state. In addition, the result Ag₃Mg is contrary with that which Nicholas’s theory suggested.

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The crystal structure of nickel carbide, Ni₃C, was studied by the electron diffraction method. The observed intensity showed considerable primary extinction and this was corrected, using Wilson’s intensity statistics combined with the theory of primary extinction (S. Nagakura, Acta Cryst. 10 (1957) 601). The actual procedure was described in detail and it was concluded that the structure of nickel carbide belongs to the space group R\bar3c and nickel atoms occupy 18e positions with the parameter x=1⁄3 and carbon atoms 6b positions. It was found also that the carbon atoms take a kind of one-dimensionally disordered arrangement in the carbide lattice.

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Germer and White (Phys. Rev. 60 (1941) 447) found that thin evaporated films of face-centered cubic metals produce electron diffraction patterns with anomalous intensities. Kimoto (J. Phys. Soc. Japan 8 (1953) 762) studied the anomaly by a trial method and attributed it to stacking faults in crystallites. By the radial distribution analysis the present author confirmed Kimoto’s conclusion.
Intensities of diffraction patterns from evaporated silver were accurately measured by the sector-microphotometer method and they were turned into radial distribution function. These functions reveal anomalous peaks caused by stacking faults. After a specimen is annealed at 350°C for 3.5 hrs., although crystallites do not grow remarkably, these peaks disappear. The amplitude of thermal vibration is found to be 0.15±0.02Å which agrees well with that for massive silver crystal. The narrowing of the first neighbor peak is found and is attributed to the correlative thermal vibration.
Gold shows the same anomaly as is observed for silver, but aluminum shows no anomaly. These facts are in accordance with the value of stacking-fault energy.

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The electron distribution in a bonded hydrogen in crystals is investigated using mainly the VB method with the Gaussian approximation to the Slater wave functions. This approximation appears to be fairly good if the thermal vibration is considerable. In the present paper is studied the C–H bond as an example. It is concluded that the position of the maximum electron density around the proton is located more or less towards the heavier atom, and hence an apparent bond contraction in the X-ray analysis should occur. This seems to be in accord with experimental results. The apparent bond shortening increases and the peak density decreases with increase in the ionic character of the bond. For a constant value of the ionic character, the magnitude of the apparent bond shortening rapidly reaches a certain constant value when thermal vibration becomes large.

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In order to determine the model of the M center, the luminescence and dichroism of additively colored KCl were studied in detail. The polarization factor of luminescence due to M centers excited with polarized light in the F band are P(π⁄4)=−0.37 and P(0)=−0.17. The F band as well as the M band becomes dichroic by irradiating with polarized light in the M band at room temperature or in the F band at low temperature, and the same quantitative relation exists between the amounts of dichroism in the F and M band for both cases.
Above results do not contradict the hypothesis that the second M band overlaps with the F band, and if this assumption is granted, it is concluded from the experiment that the symmetry type of the M center is not C_2v but D_2h. The oscillator strengths were found to be 0.65 and 0.53 of that of the F band.
If the emission due to M centers excited with light in the F band is assumed to be caused by the resonance transfer from F to M centers, in order to explain the experimental value of transfer probability, the distance between both centers must be less than the order of 10 Å.

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In the case of two-dimensional flow with wake of a perfect fluid past an oblique plate, the pressure distributions on the front surface of the plate as well as on the free streamlines are calculated, together with the shapes of the latter, by applying the method of notched hodograph devised by Roshko. The calculated values are compared with the experimental ones obtained by Fage and Johansen. It is thus found that the calculated and the observed values of the pressure distribution along the front surface of the plate coincide fairly well with each other so far as the observed base pressure is constant, but discrepancies between them increase as the angle of attack decreases.

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The ideal case of the flow past a bent flat plate with an unsymmoetric dead air region at Mach number 1, in which a streamline comes tangentially to the plate at its leading edge, is discussed by means of the simple procedure of Imai’s WKB method. Numerical results are given for several values of the form parameter.

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