The excitation functions for the triton elastic scattering from ¹²C and for the ¹²C(t, α₀)¹¹B, ¹²C(t, α₁)¹¹B and ¹²C(t, p₀)¹⁴C reactions have been measured at laboratory angles of 44.5°, 76°, 112.5°, 150°, 160° and 165° in the range of triton energy from 0.6 to 3.4 MeV. The angular distributions of elastically scattered tritons and emitted α-particles have been also measured at eighteen energies of the incident triton between 1.1 and 3.4 MeV. Prominent, broad maxima were observed in the excitation functions for the elastic scattering measured at backward angles in the region of 2.2 MeV. Twenty-one resonance-like peaks were found in the excitation functions of the reactions above described. An attempt has been made to analyze the date on the elastic scattering using the optical model.

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The angular distributions of alpha-particles and deuterons scattered elastically and inelastically by Li⁶ and Li⁷ were measured. The 2.18 MeV state of Li⁶, the 0.478 MeV and the 4.63 MeV states of Li⁷ were appreciably excited. The experimental angular distributions were analysed with the DWBA theory, and the deformation parameters of the above mentioned states were determined.
Experimental results and the DWBA analysis show the existence of some difference between the inelastic scattering of alpha-particles by Li⁶ and by Li⁷, while no appreciable difference was observed in the case of the deuteron scattering. The DWBA calculation predicts larger quadrupole deformations of the excited states of Li⁶ and Li⁷ as compared with rotational model calculations of the energy levels.

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A method is presented for finding the frequency distributions of lattice vibrations of the molecular crystals. The method is applied to solid carbon monoxide at low temperatures, making use of the observed far-infrared frequencies to check some of the molecular interaction constants, and frequency distributions are calculated. The values of heat capacity at low temperatures are evaluated using the calculated frequency distributions, and are compared with experimental data. The result shows that the treatment may be useful in discussing molecular vibrations in the lattice at low temperatures.

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Non central interactions consisting of central and angular forces, have been assumed among the first, second and third neighbours of a body centred tetragonal crystal. The secular determinant so obtained has been compared in the long wave length limit with the acoustic determinant and thus the six force constants have been related with the six elastic constants.

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The formation of an impurity band for independent electrons moving under actions of a static magnetic field and short-range potentials due to impurity centers is discussed. The theoretical basis is the disordered-lattice Green’s function formalism of Yonezawa and Matsubara. When the impurity potential is attractive and the magnetic field H is strong enough, there is at least one bound level associated with each center, which is shown to display a spread to form a band because of the presence of many impurities. The critical condition of this impurity band merging into the main band is expressed in a form of an “equation of states”. The trace of the disordered lattice Green’s function, Z(E), defined so that it satisfies a self-consistent relation between the Green’s function and its self-energy is shown to be endowed with some satisfactory analytic properties which assures the sum rule for the impurity-band density of states and other characteristics. While the imaginary part of Z(E) represents the density of allowed energy bands, the real part of Z(E) is shown to express the degree of localization of the scattered amplitude due to individual centers. On these bases a thermal distribution of electrons over both bands and the high-field conductivities are calculated.

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The one dimensional XY model of spin 1/2 is discussed by transforming the spin operators to the Fermi operators. This method can be applied to the XY model with an impurity spin. In that case a pair of localized exciton (or a kind of magnon) levels are obtained. The energy of states can be determined by distributing the excitons over two sets of exciton levels which depend on whether the number of excitons is even or odd. The energy levels of states are calculated by the computer for small rings of 4, 6 and 8 spins. The results can be perfectly understood by the theory.

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The electron spin resonance spectrum of vanadyl ion (VO²⁺) in single crystals of Rb₂SO₄ is studied. The V–O axis is found to have several possible orientations. However, in four different orientations the number of spins are more and much more as compared to the number of spins in all other orientations. The spectra due to VO²⁺ ions in these four positions have been analysed and the spin-Hamiltonian parameters at X-band are determined.

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The magnetic structure of the magnetic linear chain substance, Cu(NH₃)₄SO₄·H₂O, has been investigated by means of proton nuclear magnetic resonance and magnetic susceptibility measurements. A transition from the short range (or intra-chain) ordered state to the long range ordered state was found at 0.43±0.01°K in both measurements. The magnetic spin arrangement inferred from the rotation studies of the proton N. M. R. is nearly antiferromagnetic in a –O–Cu–O–Cu–O– chain, and nearly parallel to the c-axis. It is plausible that spins cant by few degrees from the direction parallel to the c-axis. This spin structure is inconsistent with the previous magnetic susceptibility data by Haseda and Miedema. Therefore, susceptibility measurements have been repeated taking care of the thermal equilibrium between the sample and the cooling agent in the temperature region between 4.25 and 0.03°K, and the results different from their work have been obtained, which are not inconsistent with the spin structure inferred from the proton N. M. R..

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Generalized dielectric functions for a single band model of d-electrons and a two band model of d- and conduction-electrons are obtained by the self-consistent field method and the tightly binding approximation for d-electrons in transition metals. By means of these functions, screenings of an impurity potential, namely, the effective potential and the induced charge density, are investigated. The results obtained are compared with the ones obtained by taking into account only transitions of the normal process in electronic polarization and by the Thomas-Fermi approximation. Numerical calculations for the case of an impurity in ferromagnetic nickel are carried out as an example.

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Samples of CrO₂ containing a small quantity of Fe⁵⁷ were prepared and the Mössbauer effect was measured at various temperatures. It was found that Fe atoms were dissolved in CrO₂ taking the electronic state of trivalent ion. The temperature dependence of the internal magnetic field at Fe was analyzed with using a simple molecular field approximation and the coupling between Fe and Cr was discussed. The spin direction of Fe was determined to be antiparallel to the magnetization of CrO₂ matrix by the Mössbauer measurement in an external magnetic field (45 kOe).

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Negative magneto-resistance is observed in poorly graphitized carbons at liquid nitrogen temperature or even higher. This peculiar phenomenon has been studied on pyrolytic graphite, as a model material. It is concluded that the negative magneto-resistance is a quantum phenomenon caused by a change of the carrier concentration induced by the applied magnetic field. The incentive for the change of the carrier concentration, which is unusual in itself, lies in the peculiar energy band structure of this material. Theoretical curves calculated on this conjecture reproduce the experimental results very well.

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The electroabsorption coefficient has been derived for photon energies below the band gap in the one-band effective-mass approximation using a W. K. B. treatment.

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The ionic conductivity of single crystals of pure and KCl- and NaCl-doped PbCl₂ has been measured between 90 and 400°C. The thermal disorder appears to be of unassociated Schottky defects. The expressions for the “mobility” μ and the “concentration” x_n⁰ of anion vacancies have been determined from a comparison between the observed isothermals and those predicted from the simple theory of Koch and Wagner in which association effects are omitted. The experimental expressions are
μ=(2.6×10⁻¹⁄T)exp(−0.20±0.03⁄kT) cm² volt⁻¹ sec⁻¹
and x_n⁰=2.7×10²exp(−0.51±0.05⁄kT) in mole fraction, where kT is expressed in electron-volt. These are the first results, expressed as a function of temperature, for anion vacancies in PbCl₂ crystals.

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The Na⁺L_2,3 absorption spectra of sodium halides, NaF, NaCl, NaBr and NaI, have been obtained at 300°K using a grazing incidence spectrograph with a concave grating of 2 m radius and a vacuum spark source of Vodar type as a quasi-continuum background. Sharp absorption bands due to X-ray excitons at the Γ₁ point were found at the long-wavelength edge. The doublet structure of these exciton bands was analysed, according to the theory of Onodera and Toyozawa, by the spin-orbit splitting of Na⁺L_2,3 levels and the exchange interaction between the electron and the hole of an exciton. The structure of the absorption spectra in the energy region above the exciton doublet was tentatively assigned to the absorptions arising from the formation of excitons at the point other than Γ₁ and from the transition from the Na⁺L_2,3 level to the conduction band. The possibility of the presence of the two-electron excitation was suggested.

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Intervalley electron scattering rate in a boron-doped silicon is derived through a stress-associated cyclotron resonance at 2.2°K. The method of analysis is quite complementary to that introduced in an earlier paper. It combines the down-to-up electron valley population ratio with the known value of the recombination time. The boron-assisted intervalley scattering rate is not affected by stress in the range of 0.5∼3.0×10⁶g·cm⁻².

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Recovery and recrystallization processes have been continuously observed with a 500 kV electron microscope on cold-worked aluminum foils which are sufficiently thick to cause the same phenomena as in bulk specimens. When the specimens are annealed, many of tangled dislocations become loose and form sub-boundaries at different portions from the cell walls in general. Subsequently, the subgrains grow one after the other. In these processes, attractive force of dislocation arrays on each individual composite-dislocation of other sub-boundaries plays an important role, so that the composite-dislocations of sub-boundaries with low dislocation density are generally absorbed into the neighboring sub-boundaries with higher dislocation density. At the same time, the sub-boundaries migrate by the line-tension of neighboring sub-boundaries. Through these processes, new high-angle boundaries, i.e., so-called recrystallization boundaries, are formed.

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Fine structures in absorption spectra of α-MnS single crystals are investigated at low temperatures. The sharp and temperature-independent band C: ⁶A₁→[⁴A₁, ⁴E] has five components, which can be explained in terms of covalency, descent of the crystal field symmetry and phonon-assisted transitions. In the visible and near-ultraviolet regions, five absorption bands are observed. The calculated band positions are fit for the observed bands at 4.2°K with the covalency parameter ε=0.17, the Racah parameters B=808 cm⁻¹, C=3751 cm⁻¹ and the crystal field strength Dq=1025 cm⁻¹.

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Thin films of KCl and NaCl single crystals prepared by chemical polishing were examined by an electron microscope. During the observation, the thin films were damaged by electron beam used for the image formation. As a result of electron irradiation at room temperature, plate shaped defects parallel to one of the {100} planes and elongated in one of the ⟨100⟩ directions were formed in both kinds of crystals. The maximum dimension of them was about 1 μ in long axis 1000∼3000 Å in short axis and ∼100 Å in thickness. It is supposed that these plates correspond to the small alkali metal colloids which were considered to be the origin of X-band absorption in the optical measurement, because the behaviour of the plates during heat treatment between room temperature and 300°C showed good agreement with that of the colloids.

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The light-absorbing mechanisms of the fundamental systems of trigger photoreception in animals and plants are discussed, on the basis of our calculations performed in the last several years. It is examined that chromophores of rhodopsin and phytochrome are conveniently isolated from other chromophoric groups in order to utilize light as a trigger not as an energy source, and the models for possible photoisomerizations of a non-cyclic tetrapyrrole are presented. The roles of the conformational changes of chromoproteins and of the specific interaction between a chromophore and its associated protein moiety in the cooperative excitation of the systems are also discussed, and it is shown for the case of thermal equilibrium states that the cooperativity can be brought forth from the flexible configurational state of chromophore (indicating that the state is affected by the surrounding chromoproteins through the conformational changes and the specific interaction).

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Penning ionization process is discussed from two standpoints of view, namely on the basis of quasiadiabatic and adiabatic representations of electronic states. New cross-section formulas are derived. Green operator technique is applied in the first formalism and a non-local complex potential is derived for the relative motion in the initial channel. In the second formalism Fano’s method is applied and a local complex potential is defined. In a certain limiting case these two formulas reduce to the corresponding BII approximation and the formula obtained by Katsuura, respectively. Though the first formalism is exact as it stands, it is not convenient to use this for more refined practical calculations. It is concluded that the second formalism is more suitable for practical calculations of low energy metastable Penning ionization.

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The linewidths for the 2224 cm⁻¹ N₂O band are calculated using Anderson’s theory. The mean value of the half-width is found to be 0.085 cm⁻¹ atm⁻¹ for self-broadened N₂O and 0.072 cm⁻¹ atm⁻¹ for N₂-broadened one at 300°K, respectively, by comparing the calculated widths with the measured ones. Values of the spectral absorptance computed using the quasi-random band model and a half-width of 0.072 cm⁻¹ atm⁻¹ at 300°K are in good agreement with the measurements of absorptance. The value of the self-broadening coefficient is also compared with the experiment.

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The singlet and triplet states of π-electrons in peptide group are first determined such that the ASMO–SCF–CI calculation including all the possible configurations can reproduce the observed wavelength of optical absorption maximum. It is shown that the doubly-excited configurations make a non-negligible contribution to the electronic states. Next, in terms of the Frenkel-Peierls method, the singlet and triplet exciton bands for both the H-bonded and the main polypeptide-chains in the two β-structures and in the α-helix are calculated to the second-order perturbation. It is shown that the exciton band structures are dependent only on the sorts of peptide-chains but non on the conformations, and that the interaction between bands does not exert any important effect on the structures.

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The variations of the molecular sound velocity R and the molecular compressibility B have been examined in liquid alkanes in the temperature range −20 to 200°C and at pressures upto 1400 bars. At zero pressure they showed a decrease while at higher pressures an increase. A nonlinear increase with pressure is also noticed.

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In order to confirm Joshi’s postulate that the photoelectric emission in the discharge space is a necessary primary stage in affecting the discharge current, the present study of the photo-diminution of the discharge current pulses for external electrode excitation by 60 c/s A.C. of a gas-filled phototube was undertaken specially to see whether Joshi effect was absent with the light of the frequency lower than the threshold value required for the photoemission. Besides the confirmation of the absence of the effect below the threshold frequency, the study reveals the necessity of a threshold photoemission for observing complete suppression of the discharge pulses.

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A magnetic configuration of deep well is considered, which is composed of a toroidal field and resonantly coupled helical field and multipole one. The analysis is carried out with analytical method and numerical method, taking account of well depth, rotational transform angle and mirror ratio.

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An acceleration of electron by the local electron cyclotron resonance with the non-uniform microwave and static magnetic fields has been investigated. The spatially varying microwave field is generated by (a) a standing wave in a waveguide, (b) a standing wave along a Lecher line and (c) a microwave field perpendicular to a Lecher line, respectively. In these configurations, the maximum acceleration of electrons is made with the local cyclotron resonance at the position of maximum microwave field, only when the magnetic field is decreasing in the direction of electron drift. Further, when the electron beam is accelerated, its energy distribution is spread out, compared with that in the case of no acceleration.

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The linear oscillations of a sphere in an infinite mass of compressible fluid are studied when the fluid is allowed to slip at the surface of the sphere. Several limiting cases of interest are obtained. It is found that the slippage tends to decrease the maximum drag while the viscosity tends to increase the maximum drag.

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In the present paper an attempt has been made to investigate the effects of the axial magnetic field and the axial currents on the stability of spiral flows of a non-dissipative system. A sufficient condition of stability is obtained when all the four components, namely, the swirl velocity, axial velocity, axial magnetic field and axial currents are present. In particular, the case, when the axial velocity is not present, is discussed in detail and it has been shown that the sufficient condition for stability obtained by Howard and Gupta is valid only for oscillatory modes and further the necessary condition for the existence of non-oscillatory neutral modes is obtained.

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Electrohydrodynamic flow over an insulator wavy wall is studied by the perturbation method similar to the Prandtl-Glauert method. The charged gas is assumed to be a simple one and not to have dissipative effects. For the subsonic flow, a modified M²-expansion method is applied, because the straightforward M²-expansion method gives a wrong asymptotic behavior. The surface pressure, the streamlines and the electric lines of force are calculated.

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The linearization method of Prandtl-Glauert type is applied to the electrohydrodynamic supersonic flow over a wavy wall. But it is found that it has no solutions satisfying the appropriate boundary conditions. Thus, a simplified model of an oscillating piston problem for this flow is considered. Numerical solutions of this problem are obtained as the initial value problem. The density distributions and the streamlines are calculated. It is found that sufficiently far from the piston, shocks are fully developed.

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