The expression for the electric current density induced in a system by an incident polarized beam is obtained on the basis of quantum statistical mechanical theory of linear response. It is expressed as a sum of time and space derivatives of the electric polarization and quadripole moment density and of the magnetization. In the case of the solution averaging over whole molecular orientations are applied. By solving the Maxwell equations with substitution of the averaged current density, what sort of polarized beam can travel through the solution is investigated. In the solution of randomly-oriented molecules the contribution from the quadripole moment density vanishes and the usual theory for the solution is attained. In the uniaxially symmetric case of molecular-orientation probability a linearly polarized beam travelling in the direction of the symmetry axis exhibits the optical rotation and circular dichroism, where the quadripole moment density contributes to the phenomena.

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It is pointed out that concentration fluctuations affect the magnetic properties of Fe–Ni Invar alloys, which behaves as collection of cells containing equally 60 atoms whose mean concentrations are different from cell to cell. The fluctuation can be expressed by a Gaussian distribution law when the proportion of the number of the cells having the same concentration is plotted against the mean concentration.
The saturation magnetization vs. nickel concentration relation, the deviation of the magnetic saturation moment σ vs temperature T curves form the standard Brillouin function, the small thermal expansion coefficient around room temperature and other anomalous physical properties of the alloy were accounted for on the basis of the present model of the concentration fluctuations.

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Magnetization, Mössbauer absorption spectra and lattice constants have been measured on the γ phase (f.c.c.) Fe–Ni alloys of 20∼30 at% Ni using finely grained samples in which the γ→α martensitic transformation can be suppressed even at liq. He temperature. The magnetic moment decreases very sharply from 1.3μ_B in 30 at% Ni to 0.2μ_B in 20 at% Ni. The Mössbauer absorption spectra observed at liq. He temperature show the appearance of antiferromagnetism in the low nickel concentration range. These experimental facts indicate that in these composition range the alloys consist magnetically of two phases, namely ferromagnetic and antiferromagnetic ones. This magnetic heterogeneity is caused by the statistical concentration fluctuation and is discussed quantitatively by considering a Gaussian type concentration distribution. The temperature and composition variations of the lattice constant and the thermal expansion coefficient can also be interpreted quantitatively on the basis of the same Gaussian type concentration fluctuation.

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Forced longitudinal and transverse magnetostrictions for polycrystalline Ni have been measured by strain gauge technique at temperatures from 200 to 613°K below the Curie point. Results obtained show clearly an anisotropy, so that the forced volume magnetostriction is turned out not to be equal to three times as large as the forced longitudinal magnetstriction. The temperature dependence of the forced volume magnetostriction obtained reliably shows to be positive below T⁄T_c≅0.7 and negative above it. The forced volume magnetostriction at 0°K, (∂ω⁄∂H)₀=1.4×10⁻¹⁰ Oe⁻¹, and the change of the Curie point with pressure, ∂T_c⁄∂p=3.2×10⁻⁴ deg/bar, are estimated thermodynamically and agree with Kondorsky’s results and with Patrick’s, respectively. A special attension is given to an anomalous thermal expansion near the Curie point.

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Magnetic properties of single crystal of CsCuCl₃, CsNiCl₃, RbNiCl₃, CsCoCl₃, and RbFeCl₃ were investigated by the measurements of magnetic susceptibilities, magnetic torques, ESR absorptions from liquid helium temperature to room temperature. The experimental results were interpreted in terms of linear antiferromagnetic chains, taking into account the effect of crystal field. The anisotropic exchange interaction energies between the neighboring magnetic inos along a chain were estimated to be J_⁄⁄⁄k=−7.0°K, −11.0°K, −14.1°K, −85°K, and −11.5°K, and J_⊥⁄k=−6.0°K, −11.0°K, −14.1°K, −17.0°K, and −3.8°K, for CsCuCl₃, CsNiCl₃, RbNiCl₃, CsCoCl₃, and RbFeCl₃, respectively by the comparison with the calculated susceptibilities for linear antiferromagnetic chains with Heisenberg and Ising spins by Bonner, Fisher et al.. Properties which appeared in short range magnetic order were studied for two nickelous compounds above T_N, 4.5°K in CsNiCl₃ and 11°K in RbNiCl₃. A qualitative discussion of the exchange interaction in these compounds is given.

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The magnetization, the flux flow resistivity and the Hall voltage have been measured for three vanadium specimens with different purities. The parameters pertinent to the magnetic properties of type II superconductors near the upper critical field H_c2—the Ginzburg-Landau-Maki parameters κ₁ and κ₂, and the Helfand-Werthamer parameters h^* and (dh⁄dt)—were obtained from the data. It was found that the values of κ₁, κ₂ and h^* at 0°K increased with increasing purity and the magnitude of the increase of them was larger than the value expected from the microscopic theory. This discrepancy between experiment and theory seems to correspond to the effect of the non-spherical Fermi surface suggested by Hohenberg and Werthamer. Resistivity measurements showed that with increasing purity, the behavior of the slope of the flow resistivity near H_c2 changed from that of the dirty material predicted by Caroli-Maki to that of intermediate material. This result is different from the Kim’s empirical relation. The Hall angle in the mixed state is found to be strongly dependent on the electron mean free path.

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Effects of the magnetic impurity on superconducting properties were investigated on the La_3−xGd_xAl system. The superconducting transition temperature T_c, the upper critical field H_c2 and the magnetic susceptibility in the normal state were measured for various concentrations of gadolinium. A remarkable departure of the T_c versus impurity concentration curve from the Abrikosov-Gor’kov curve was found in the region of high impurity concentrations (>0.4 at.% GD). Magnetic susceptibility versus temperature curves of compounds with Gd concentrations large enough to suppress the superconductivity showed no peak above 4.2°K. The H_c2 versus temperature curve of the compound with 0.3 at.% Gd crossed the curve of La₃Al. The upper critical field at 0°K, H_c2(0), had a maximum at a certain Gd concentration near La₃Al. This fact is qualitatively explained by the theory of Fulde-Maki.

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The low temperature transition of α′-MnZn₃ alloy of Cu₃Au type structure has been investigated by X-ray and neutron diffraction experiments, dilatometry, magnetization measurements and specific heat measurements. This alloy exhibits antiferromagnetism below 130°K, at which the cubic lattice is transformed to the tetragonal lattice, the axial ratio c/a being 0.95. On heating, both the tetragonality and sublattice magnetization vanish abruptly, indicating that this transition is of the first kind. The integrated value of the anomalous specific heat and the entropy change due to the transition are in rough agreement with those calculated by taking only the magnetic contribution into account. Apart from this transition, the field dependence of susceptibility becomes appreciable below 170°K, and the remanent magnetization appears below 60°K. These behaviours are probably due to the stacking fault in the fcc lattice, since the corresponding hcp lattice of metastable ε′-MnZn₃ is ferromagnetic.

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The interband effect on the steady magnetic susceptibility is calculated by a new method for a perfect crystal in which the periodic potential is assumed to be one-dimensionally sinusoidal. The results are compared with those of Adams who treated the same model.

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The pressure dependence of the Ginzburg-Landau parameter, κ, in some second-kind superconductors was measured. Pressures up to 3,000 atm were applied using a high pressure bomb with kerosene-oil mixture as the transmitting medium.
For Pb-3.5 at.% Tl and Pb-3.5 at.% In, dlnκ⁄dp is −12.6±1.8 and −12.1±4.5×10⁻⁶ atm⁻¹, respectively. The Gor’kov formula, which connects κ with the electronic specific heat coefficient, γ, and the residual resistivity, ρ, is well satisfied with the observed values of dlnκ⁄dp, dlnγ⁄dp and dlnρ⁄dp.
The difference in the pressure effect on the effective electron-electron interaction parameter between the above two alloys was found to be greater than that on γ, which is proportional to the density of states at the Fermi level.
The pressure dependence of the upper-critical field is in good agreement with the data calculated from the bulk modulus jump.

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The four solid-solid phase transformations in the cooled melts of RbNO₃ and its solid solutions, Cs_xRb_1−xNO₃, and K_xRb_1−xNO₃ are examined by electrical conductivity measurement, differential thermal analysis (DTA), dilatometry and X-ray diffraction technique. The solubility of CsNO₃ of KNO₃ in RbNO₃ is explained on the basis of similarity of phases of RbNO₃ with those of CsNO₃ or KNO₃. With increasing x, in the systems Cs_xRb_1−xNO₃ and K_xRb_1−xNO₃, the transition temperature IV→III remains nearly unaffected whereas the III→II shifts at a faster rate compared to the II→I transition. This is interpreted in terms of (i) the crystallography of different phase of RbNO₃ and (ii) the variation of the cation to anion radius ratio with x in the solid solutins. Coexistence of phases III and II in the (Remark: Graphics omitted.) transition region is studied.

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Single crystals of NaNO₂ were irradiated with Co⁶⁰ gamma-ray of 1–6×10⁸ R at room temperature, then the dielectric constant ε₂₂ was measured in the vicinity of the transition temperatures. Both the ferroelectric to sinusoidal transition point (the Curie point) and the sinusoidal to paraelectric transition point (the Néel Point) monotonically decrease with gamma-ray irradiation. The ratio of the initial decreasing rate of the Curie point to that of the Néel point is 1.21. The sinusoidal phase widens with irradiation up to 2.5×10⁸ R, then it narrows with more irradiations. The transitions become sluggish with irradiation dose more than 2.5×10⁸ R.

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Temperature dependence of the spontaneous polarization, P_s, of a few polycrystalline samples of antimony sulfo-iodide between −178 and 20°C is reported. An anomaly is observed in the behavior of the spontaneous polarization with respect to temperature for the samples between −178 and −10°C. In this region P_s increases with increasing temperature and then falls rapidly obeying the law: P_s²∝(T−T₀). The coercive field, however, decreases with increasing temperature. The Curie point and the paraelectric temperature are found to be 22 and 29°C respectively. The discrepancy in the values obtained for the crystals grown with and without an electric field is discussed.

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The coupling between the N=1 Landau level and the N=0 Landau level +one LO phonon continuum is investigated by the Green’s function method under the condition that the cyclotron frequency ω_c is nearly equal to the LO phonon frequency ω₀. The spectral weigh function is shown to have a peak above the threshold of the continuum for any value of ω_c, in contrast to the behavior of the solution of the WB perturbation and the pole of Green’s function. Cyclotron resonance line profile is calculated as a function of ω_c for ω<ω₀ and at liquid nitrogen temperatures. Calculated line width is finite at ω=ω₀ and decreases with temperature. Transverse magnetoresistance by absorption of thermal LO phonons is calculated as a function of ω_c taking fully into account collision broadening of the N=1 Landau level due to LO phonon emission. The result is free of divergence at ω_c=ω₀. A shift of the position of the maximum to the high ω_c side is predicted. Though qualitative agreement with experiment is good in the both phenomena, absolute magnitude of the line width and the magnetoresistance is smaller than the experimental one by a factor about 1.5, which suggests a larger value of the coupling constant than the one estimated from Fröhlich’s formula.

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Magnetic circular dichroism (MCD) and stress dichroism (SD) in the absorption spectrum due to (s)²→(s)¹(p)¹ transition with electron lattice interaction have been theoretically studied in order to investigate the further consequence of the Jahn-Teller effect in the excited state. In the framework of the classical Frank-Condon approximation, dichroic absorption spectra have been numerically calculated by means of the Monte Carlo integration over the five-dimensional “interaction-mode” coordinate space. Calculated dichroic spectra are consistent with the existing data for the line shapes of MCD and SD in the Tl⁺-like centers in alkali halides.

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The results of a series of reflectivity and absorption measurements performed to clarify respectively the excitonic transitions in the intrinsic region to 13.5 eV and the thermal and spectral dependences of absorptions in the tail region of LiF, NaF, KF, CaF₂, SrF₂ and BaF₂, each being cleaved from Harshaw blocks of single crystal, are presented. The tails of Harshaw LiF, being expressed by exponential functions of energy in the range of 10⁰ cm⁻¹\lesssimA\lesssim5·10² cm⁻¹ and 300°K≤T≤573°K, have turned out to be extrinsic to LiF. The present experiments could not provide sufficiently conclusive evidences in clarifying the question whether the tails of Harshaw alkaline earth fluorides, to Urbach rule is applicable for the range of 10⁰ cm⁻¹\lesssimA\lesssim10² cm⁻¹ and 78°K≤T≤573°K, are intrinsic. In the first peak of reflectivity spectra, the fluorine doublet with ∼0.05 eV separation is detected for KF and quintet structure for SrF₂ and BaF₂. In the latter, the lower energy lying doublet was identified with the Γ-exciton (fluorine doublet) and the remaining triplet with the X-excitons. The apparent doublet in the first peak in CaF₂ is inferred to result from the unresolved quintet lines. The oscillator strengths for the first peak as a whole were estimated by means of Kramers-Kronig transform of reflectivity spectra: they are 0.52 for CaF₂, 0.47 for SrF₂ and 0.44 for BaF₂.

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The microwave harmonic generation in n-type germanium is observed at liquid helium temperatures and it is found that the third harmonic generation (THG) shows the resonance behavior when the magnetic field is changed. The experimental results on the conversion efficiency, anisotropic behavior of the peaks, donor concentration dependence and the input power dependence of the THG are described. It is shown from these characteristics that the resonance type THG arises from the multi-photon resonance of electrons trapped in very shallow impurity states. A model is proposed that such impurity states are the states associated with the donor negative ion (D⁻), and the anisotropic behavior of the resonance field is reasonably interpreted in terms of the orbital Zeemann effect of the D⁻ states.

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The results of the reflectivity and absorption measurements on NaF single crystals (Harshaw) at 78°K and at room temperature are presented. The fluorine doublet, and the side band structure which is located at the higher energy side of the former and is presumably due to the transition of simultaneous creation of exciton and phonon, are observed in the reflectivity spectrum at 78°K. The spectra of optical of constants derived from these reflectivities by means of the Kramers-Kroning relation are also presented. It is shown that the fluorine doublet can be decomposed into two asymmetric Lorentzian lines with the oscillator strengths 0.155 and 0.215 for the lower and higher energy components, respectively. The position of the first reflectivity peak of (²S_1⁄2, ²P_3⁄2), determined in the temperature range of 10°K to 295°K, is found to be well fitted by the formula of Bose-statistics. The empirical relation which is capable of representing the thermal shift of the first exciton peak of all alkali halides is proposed, and is discussed from the viewpoint of exciton-phonon interaction. On the basis of this relation, the thermal and spectral dependences of intrinsic absorption tails of LiF are discussed.

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Nyquist noise voltage of triglycine sulfate single crystals is measured as a function of temperature at various frequency range. Dielectric constants for zero external fields are determined in the close vicinity of the Curie temperature. No dielectric dispersion was found around such a low frequency as 1 kc/s, contrary to the result of Brophy and Webb.

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The Fourier coefficient of the line profile of a Debye-Scherrer ring broadened by lattice distortion is given as the product of two factors, one of which is due to the fluctuation in the average strain of each particle in the powder and the other is due to the inhomogeneous strain, i.e. the displacements of the unit cells from the average sites. The line profile is of Cauchy type in the case of no fluctuation in the average strain of each particle in the powder, even though the distribution of the displacements is of Gaussian type.

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Shifts of the electron diffraction spots of the plastically deformed β′ martensite of Cu-11.04wt.% Al alloy have been examined using the selected-area diffraction method of an electron microscope. The analysis of these shifts shows the existence of various states of stacking disorder corresponding to α=0∼0.6 where α is a stacking fault parameter representing cubic type stackings. The states of staking disorder corresponding to α=0.6∼1.0 are not found; instead there exist structures which are expressed as (7\bar1), (8\bar1)₃, (10\bar1) and (11\bar1)₃ by Zhdanov notation. These structures are considered to be energetically more favorable than the f.c.c. structure for the alloy used.

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π-electronic structures of the base pairs of DNA are determined in the framework of Frenkel-Davydov’s exciton theory including double excitations. The π-electron densities in the ground and the excited states and he excitation energies and oscillator strengths are discussed in comparison with those of the component bases. The hyperchromic effect is found in the transition to the lowest excited states and the slight blue shift in A–U pair and somewhat appreciable blue shift in G–C pair are found. Further, the interaction energies between pairing bases are estimated in terms of generalized charge densities of component bases which were calculated using the best available π-electron molecular orbitals obtained in our previous work. The π-electronic stabilization energy of base pairs mainly results from the interaction between the permanent charges in the atomic sites of the bases and it is found that G–C pair is more stable than A–U pair.

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Singlet exciton states double stranded homopolynucleotides and copolynucleotides are determined within the framework of Frenkel exciton model taking into account the effect of configuration mixing between different exciton states. Interbase interactions are taken into account up to the distance of the order of 15 Å and they are calculated directly using the generalized charge densities in the base pairs previously obtained by the authors. The exciton states of model DNA is also discussed in which two kinds of base pairs are arranged in random order. Generally the oscillator strength associated with the lowest exciton states decreases by the effect of configuration mixing. There can be found no weak π→π^* transition near 280 mμ in poly (A–U) and copoly (Remark: Graphics omitted.). In a model DNA the absorption intensity in the long wave length side of the main absorption band depends linearly on G–C content.

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Calculations have been made of the molecular sound velocity, R, and molecular compressibility, B, liquid metals (Cu, Cd, Zn, Bi, Sn and Sb) in order to investigate their temperature variations. Except for Cu, in all other liquid metals R and B showed a non-linear increase.

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The propagation of ion waves externally excited by a gridded electrode in a nonuniform plasma is experimentally investigated. The nonuniformity of the zeroth order drift velocity of ions plays dominating role rather than that of the density in this plasma. The acceleration of ions along the direction of the propagation of ion waves in the presence of the ambipolar field causes an increase in its phase velocity and also an attenuation of the density perturbation. The attenuation is a attributed partly to the loss of the wave momentum due to nonuniformity and partly to an ionization. These new phenomena are examined quantitatively on the basis of the fluid equations using W.K.B. approximation and a rigorous numerical computation.

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In rf discharges of 14–50Mc/sec under an axial magnetic field up to 100G, waves are excited by applying sinusoidal currents of 1–100 kc/sec to a small coil surrounding the discharge tube. The waves exhibit standing wave patterns, in spite of absence of reflection, along the plasma column. The wavelengths are independent of the ion mass density and the coil current frequency. They are proportional to the plasma radius, the magnetic field intensity, and the inverse of the discharge frequency. Agreement if found with the theory for space charge waves in a bounded plasma, whose frequencies are equal to the discharge frequencies. Those space charge waves, modulated in amplitude, are shown to be excited by the local density modulations produced by the coil currents in the presence of the rf discharge field. The standing wave patterns are attributed to the synchronization of the waves with the rf discharge field.

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The influence of collisions on the onset and linear stage of the ion-acoustic instability in a dc-discharge in Helium is studied experimentally. The threshold values of the drift velocity and frequency and the range of the unstable frequency spectrum are in good agreement with the values calculated from the dispersion relation based on the Vlasov equation with inclusion of ionneutral collision. The intensity of charged particle density fluctuation has been measured over 4 orders of magnitude covering the range from thermal level to the fully developed instability.

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The effects of uniform parallel magnetic field upon the stability of a free boundary layer of an incompressible, electrically conducting fluid with small magnetic Prandtl number γ are investigated for flows of large Reynolds number R: The condition for stabilizing the disturbance with the wave-number α is obtained as a relationship between N(=γRA², A: the Alfvén number), αR and γ.

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The transient heat transfer near a two dimensional stagnation-point in a steady flow of a viscous and incompressible fluid is considered. The temperature of the fluid is assumed to change abruptly from a constant to another constant. Two cases are investigated by means of Liepmann’s approximate method. In the first case the temperature of the wall is assumed to be a constant and in the second case the rear surface or the thin wall to be adiabatic. The time histories of the heat transfer coefficient for both case and of the temperature of the wall for the second case are obtained. Discussions on the validity of the latter are given.

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The boundary value problem of helicon wave propagation in a square rod of infinite length with a longitudinal magnetic field is solved by using a variational method which is based on the conservation of the complex Poynting vector. The dispersion relation obtained under the assumption of a lossless plasma agrees very well with the experimental observations of C. Nanney.

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