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In this paper, a combined numerical–experimental methodology for the identification of elastic moduli of orthotropic media is presented. Special attention is given to the laminated electrical steel sheets, which are modeled as orthotropic media with nine independent engineering elastic moduli. The elastic moduli are determined specifically for use with finite element vibration analyses. We propose a three-step methodology based on a conventional nonlinear least squares fit between measured and computed natural frequencies. The methodology consists of: (1) successive augmentations of the objective function by increasing the number of modes, (2) initial condition updates, and (3) appropriate selection of the natural frequencies based on their sensitivities on the elastic moduli. Using the results of numerical experiments, it is shown that the proposed method achieves more accurate converged solution than a conventional approach. Finally, the proposed method is applied to measured natural frequencies and mode shapes of the laminated electrical steel sheets. It is shown that the method can successfully identify the orthotropic elastic moduli that can reproduce the measured natural frequencies and frequency response functions by using finite element analyses with a reasonable accuracy.

This paper presents a topology optimization method which is capable of designing both topology and orientation distribution of anisotropic composite material simultaneously. Topology optimization is a well established structural optimization framework which optimizes the material distribution, i.e. density, in a given design domain for maximum performance. However, a method for structures made of inhomogeneously distributed anisotropic composite material is still under research. In this paper, a topology optimization method is extended to handle orientation distribution together with density distribution. A tensor field design variable is used for modeling orientation based on the idea of the orientation tensor. All tensor components are updated in similar manner to the Free Material Optimization technique while maintaining the physical feasibility by using the existing material tensor for interpolation. Thanks to the tensor representation, the method is free from complications derived from three-dimensional rotation. At the same time, the method works well with common non-linear programming algorithms because the tensor invariants are kept constant by multi-variable projection without point-wise constraints. The proposed method is built upon a modern topology optimization technique, thus, it is versatile and flexible enough to solve multi-load problems. Single loaded and multiply loaded stiffness maximization problems are provided as numerical examples, and characteristics of concurrent density and fiber orientation optimization are investigated.

We performed the STM Spectroscopy (STS) measurement on organic superconductor deuterated κ-(ET-d[3,3])2Cu[N(CN) 2 ]Br to clarify the mechanism of superconductivity. The mechanism of superconductivity in κ-ET2X is predicted as the spin fluctuation mechanism where the gap symmetry changes from d x 2 − y 2 to dxy with increasing the electron correlation. In previous STS measurements, we found that d[2,2]-Br, d[0,0]-Br and Cu(NCS)2 were d-wave superconductors and the symmetry was described by the d x 2 − y 2 . The electron correlation of these salts is still weak in the frame of the spin fluctuation model. So, we investigated the d[3,3]-Br which located at stronger electron correlation region than the previously studied salts by the STS. We also investigated the STS on the cut lateral surfaces by the focused ion beam (FIB) method to measure the in-plane anisotropy of superconducting gap in more detail as well as the as-grown surfaces. It was found from the result that d[3,3]-Br was d -wave superconductor and the gap symmetry was d x 2 − y 2 as well as the previously studied ET salts. Therefore, d[3,3]-Br is also still weak in spite of stronger electron correlation than other ET salts. On the other hand, we also observed the two-type superconducting gaps which are the nodal and anti-nodal type gaps at the same angle surface. This suggests the coexistence of d x 2 − y 2 and dxy. It may be the evidence of the change from d x 2 − y 2 to dxy caused by the locally stronger electron correlation around the anti-ferromagnetic insulating region.

The kinetic energy of α′-(BEDT-TTF)2IBr2, α-(BEDT-TTF)2I3, and α-(BEDT-TTF)2NH4Hg(SCN)4 was estimated from the room-temperature optical conductivity measured from 50 to 30 000 cm−1. The kinetic energy of α′-(BEDT-TTF)2IBr2 was significantly smaller than that of α-(BEDT-TTF)2I3 that shows metal–insulator phase transition. A clear hysteresis was found in the magnetic susceptibility near the phase transition at around 30 K.

The low temperature phase in (EDT-TTF)2AuBr2 was investigated by 1H NMR and magnetic susceptibility measurements for protonated and partially deuterated single crystals. Two sharp peaks were observed in the temperature dependence of T 1 − 1 for both salts, associated with the SDW transition TSDW and the sub-phase transition T* common in the incommensurate SDW phase. The values of TSDW determined as 15 and 19 K for h- and d-salts, respectively, indicate the negative chemical pressure effect. The obtained ratios T*/TSDW 0.37 and 0.43 for h- and d-salts, respectively, are slightly larger than the common value T*/TSDW≅0.3 observed in (TMTCF)2X. The ratio T*/TSDW increases for larger TSDW and the low temperature sub-phase becomes more stable.

It is said that the quasi-two dimensional organic conductor ( BEDT-TTF ) 2 X forming two columns structure like α or θ salts, shows charge order (CO) state at low temperature. To confirm the existence of the CO state and the electron magnetism in α ′ phase whose symmetry is different from that of α and θ phases, we investigated 13 C-NMR on α ′ ‐ ( BEDT-TTF ) 2 IBr 2 , in which one-sided central carbon on BEDT-TTF molecules is substituted with 13 C. As a result, the change of spectrum was observed at 200 K which corresponds to CO transition and the angular dependence of spectrum at 15 K indicated that the charge ordering pattern was intra-column separating type. The spectrum in paramagnetic state can be examined by not only the difference of the charge density on on-site molecule but also the contribution from off-site molecules. This result suggested that the hyperfine coupling tensor changes after CO transition in which the charge separates extremely.

We report the electron tunneling spectroscopy on partially deuterated κ-(BEDT-TTF-d[3,3])2Cu[N(CN)2]Br using a low temperature STM. In the superconducting state, tunneling spectra show the energy gap structure clearly; the conductance around the zero bias voltage is well reduced. V-shaped tunneling conductance curve inside the gap edge suggests the gap anisotropy. The linear dependence on the energy near zero bias is explained by the d-wave pairing with line nodes. By fitting to the d-wave gap model, we obtain the gap parameter as Δ=1.4–3.3 meV. Correspondingly, 2Δ/kTc is estimated as 2.7–6.4. The value is almost the same as that in κ-(BEDT-TTF)2Cu(NCS)2, d[0,0] and d[2,2] salts. The zero bias anomaly, which is an evidence for nodes of the superconducting gap, was found. The d-wave symmetry is strongly supported.

Raman and infrared-reflection spectra of κ -(BEDT-TTF) 2 Cu(N(CN) 2 )Br and its deuterated and partially deuterated analogues were measured at temperatures between 5 and 300 K and cooling rates from 1 to 20 K/min. It was found that, in partially deuterated samples, the interdimer electron–molecular vibration splitting of ν 3 mode in Raman spectra, and linewidths of some phonon peaks both in Raman and infrared spectra depend on the cooling rate. These observations were explained by disorder-related effects.

We measured the polarized Raman spectra of θ-(BEDT-TTF) 2 RbZn(SCN) 4 (RbZn) and (BEDT-TTF) 3 CuBr 4 (CuBr) to investigate the detailed property of charge ordering (CO), and discussed an approach for analyzing the vibrational spectra of CO systems. The Raman spectra of the two compounds showed multiple peaks around the CC stretching region. With the help of isotope-shift measurements, the multiple peaks of RbZn were assigned to two symmetric CC stretching modes, called ν 2 and ν 3 . We used the vibronic signals of ν 3 to characterize the spatial symmetry of charge distribution, and employed the peak frequencies of ν 2 with weaker vibronic coupling effect to the estimation of charge disproportionation ratio. Similar spectral analysis was applied to CuBr salt to verify whether the approach can be applied to other systems.

This paper presents an analysis of noise occurrence at the 7th main bearing of an inline six cylinder diesel engine. From experimental results of the engine, it seems that cavitation in the bearing oil film is a major factor for this noise, and the noise occurs with a combination of the following conditions; (1) cavitation exists in oil film at the main bearing, (2) main journal is unstable and (3) excitation force acts at this moment. This assumption is analyzed using engine vibration analysis, EHL analysis and stability analysis. The results agree with the condition of the noise occurrence.

This paper considers the generalized algebraic Riccati equation (GARE) associated with a non-standard J-spectral factorization problem (NS-J-SFP) for descriptor systems, of which system matrices have full column rank. We derive necessary and sufficient conditions for the existence of a semi-stabilizing solution of the GARE based on the Hamiltonian matrix pencil approach and gives a parametrization of all the semi-stabilizing solutions. Then we provide a nonstandard J-spectral factor (NS-J-SF) in terms of a particular semi-stabilizing solution of the GARE. A simple numerical result is also included.

A thermodynamic investigation on the electronic properties of several organic salts based on BEDT-TTF and DCNQI molecules is performed by means of high-precision specific-heat measurements in the temperature range between 0.9 and 6 K. The electronic specific-heat coefficient γ for dimeric insulators is almost 0 mJ/mol K 2 , which is explained by the picture of Mott–Hubbard gap in the effectively half-filled band. The non-dimeric salt of (DI-DCNQI) 2 Ag, on the other hand, shows an unexpectedly large γ value of about 30–40 mJ mol −1 K −2 representing the existence of large low-energy excitations from the charge-ordered insulating ground state. The difference of the low-temperature electronic specific-heat behavior between the dimeric and non-dimeric systems demonstrates that manifestation of electron correlation effects is qualitatively different in these systems.

We measured the 13C-NMR spectrum and T 1 of κ -(BEDT-TTF) 2Cu(NCS)2 under pressure. Both of Knight shift and 1 / T 1 T showed the temperature independent behavior at low temperature under all pressures, therefore it is suggested that this material behaves as Fermi liquid at this region. Pressure dependence of Knight shift at low temperature cannot account the strong pressure dependence of the m c * , which observed by Shubnikov–de Haas (S–dH) measurement. On the other hand, pressure dependence of Korringa factor, calculated from Knight shift and 1 / T 1 T , is similar to that of the m c * . These results suggest that anti-ferromagnetic (AF) fluctuations contribute to the superconductivity in this material.

In recent years, concern has been raised about the charge fluctuation of the superconducting transition in the loosely dimerized molecular conductors. Not only the observation of the charge fluctuation is of considerably important but also the understanding of the mechanism of the fluctuation. We have observed degree of charge fluctuation of several β''-type ET salts. The β''-type ET salt is one of the best model compounds because the direction of the largest inter-site Coulomb interaction is perpendicular to that of the largest transfer integral. This structural property allows us to examine the role of inter-site Coulomb interaction from the viewpoint of the inter-molecular distance. The difference in the molecular charges between the charge rich site and the charge poor sites, Δρ, is correlated with the conducting behavior; the superconducting materials have the small but finite Δρ, whereas Δρ of the insulating (metallic) materials is large (almost zero). After the analysis of the configuration in the inter-molecular distances, we have found that the degree of fluctuation, Δρ, is attributed to the number of the most stable charge distribution(s), NS, and the number of the energy levels of the allowed charge distribution, NA. The superconducting materials belong to the condition of N ≥2 and N ge;2. Indeed, this condition contributes to the fluctuation of the molecular charges. © 2010 Elsevier B.V. All rights reserved.

The low-frequency dielectric constant was measured in the pressure induced incommensurate SDW phase of (TMTTF) 2 Br in order to investigate the dynamics of the SDW. Under the pressure above 0.5 GPa, the huge dielectric constant attributed to the motion of the SDW were observed. The temperature dependence of the real part of the dielectric constant ɛ ′ whose amplitudes grow with decreasing frequency shows the peak behavior in the incommensurate SDW phase. In contrast of the case of (TMTSF) 2 PF 6 , the peak temperature of ɛ ′ is constant, irrespective of the frequency. These peak temperature T P are scaled as T P / T SDW ∼ 0.3 irrespective of pressure for the pressure larger than 0.8 GPa and is associated with the sub-phase transition in the incommensurate SDW proposed by the NMR measurement. The dielectric properties are probably connected with the co-existence of the CDW component proposed for high temperature sub-phase.

We assessed 13C-NMR measurements in an organic salt, κ ‐ ( BEDT ‐ TTF ) 4 Hg 2.89 Br 8 , which exhibits superconductivity at 4.3 K under ambient pressure. We observed that ( T 1 T ) − 1 of H // and ⊥ layer at ambient pressure increased as the temperature was decreased to 7 K, but decreased further at lower temperatures, suggesting that the decrease of ( T 1 T ) − 1 was not due to the superconductive fluctuations, but due to the magnetism of the conduction electrons. Application of pressure suppresses ( T 1 T ) − 1 , with ( T 1 T ) − 1 becoming constant above 2 GPa. These results suggest that applying pressure alters the electron system from a non-Fermi liquid (NFL) to a Fermi liquid (FL) state and that antiferromagnetic fluctuations contribute to the origin of NFL behavior. Whereas most organic conductors show Fermi liquid behavior, this salt is an organic superconductor that shows NFL behavior due to the antiferromagnetic fluctuations.

The resistance and Hall resistance measurements have been carried out in the organic compound (TMTTF)2Br for various pressures. For the incommensurate SDW phase of (TMTTF)2Br stabilized above 0.5 GPa, the sign reversal of the Hall resistance was observed with decreasing temperature. In addition, a large hysteresis of the Hall resistance was observed above T*∼0.3TSDW, where TSDW is the SDW transition temperature. This behavior is possibly related to the sub-phase structure of incommensurate SDW phase, where the coexistence of the charge–density wave with the SDW was proposed for high temperature sub-phase. On the other hand, this type of hysteresis is not observed in the (TMTSF)2PF6 compound. These differences in both salts can be explained by taking into account the difference of the ratio of charge–density wave for high temperature sub-phase.

This paper considers a J -spectral factorization problem for a rational spectral matrix. The problem is called the standard J -spectral factorization problem ( S - J - SEP ) since it is applicable to the standard H ∞ control for a descriptor system (DS). A solution to the S - J - SFP is provided in terms of a stabilizing solution of an indefinite generalized algebraic Riccati equation (GARE). The main result of this paper includes the well-known result on the canonical J -spectral factorization problem ( C - J - SFP ).

The pressure dependence of the optical reflectivity spectrum [ R ( ω ) ] of deuterated κ - ( BEDT - TTF ) 2 Cu [ N ( CN ) 2 ] Br ( d 44 ) at T = 4.5 K was determined. At the ambient pressure, d 44 under fast cooling conditions forms an antiferromagnetic insulator (AFI) phase, as confirmed by the wavenumber of the ν 3 ( a g ) vibration mode. At the pressures in the range of several MPa, the optical spectrum changes to that of a metal that matches a non-deuterated material consisting of AFI and PM (paramagnetic metallic) spectra. This indicates that the phase separation between the AFI and PM phases appears at intermediate pressures. The phase size of the separated phase is smaller than the instrumental spatial resolution of 50 μ m , based on the inability of our methods to record it.

The interaction between/among operators must be considered in research domains such as a task analysis or human modeling of a teamwork operation. This paper shows that the interaction between/among operators can be represented by three kinds of "Mental Images" and operator's cognitive activity can be analyzed by using these mental images. Furthermore, it also shows (1) how mental images are formed in an operator's mind and (2) what kind of action would be taken when he/she senses a discrepancy between mental images. Finally, an illustrative example of an airplane accident shows how to make use of mental images in human error analysis.

Zero-field μSR measurements on the antiferromagnetic Mott insulator β ′-(BEDT-TTF) 2 ICl 2 were performed in order to study the microscopic magnetic properties of this organics. The volume fraction of the antiferromagnetic phase was found to be temperature independent. Muon precession frequency, which is proportional to the magnitude of the magnetic moment at the dimer of two BEDT-TTF molecules, does not follow the simple model based on the mean-field approximation.

The IR and Raman spectra of β″-(ET)3X2 [X = HSO4 and ClO4] salts were measured at various temperatures below 300 K. The ν2 and ν27 modes exhibit the splitting into two peaks below the metal–insulator transition temperature. This phenomenon is ascribed to the charge ordered (CO) state. The CO patterns of the presented compounds were determined on the basis of the numerical calculation of the vibronic ν3L mode. The assignment of the ν27 mode of ET+ was confirmed through the measurement of the reflectance spectra of the 1:1 salts (ET)ClO4, (ET)AuCl2Br2 and the isotope analogues. The ν27 mode is the efficient probe to the site charges of the ET salts.

Synthesis of deuterated and 13 C -enriched BEDT-TTF, and the results of 13 C NMR (nuclear magnetic resonance) measurement of κ-(BEDT-TTF)2Cu[N(CN)2]Br salt are reported where BEDT-TTF is bis(ethylenedithio)tetrathiafulvalene. We synthesized the BEDT-TTF molecule 13 C -enriched on only one side of the central carbon sites. By using this molecule, we could avoid the Pake doublet and estimate the density of states from the Knight-shift and the spin–lattice relaxation rate. The reduced mass effect predicted from the specific heat measurement was not observed in the 13 C NMR measurement.

A π–d hybrid electronic system, (DMe-DCNQI)2Cu, where the π orbital of the organic molecule, DMe-DCNQI, is strongly hybridized with the dxy orbital of Cu, has been studied by 15 N and 13 C NMR at three sites. The analysis of Knight shift, K, and local spin susceptibilities in the π and d orbitals was carried out separately. The π and d spin susceptibilities were found to be quite different in magnitude and temperature dependence. Moreover, the Knight shift was separated into those of two constituent bands; a one-dimensional π band and a three-dimensional π–d band. The relative weight of the band susceptibilities is strongly temperature dependent.

We reported design and synthesis of new peri-condensed heterocycles which do not contain TTF type conjugated systems, that is, three isomers of dithiaperylenes (DTPR), one isomer of dithiapyrene (DTPY) and their methylthio or methylseleno derivatives. These donors showed two-stage redox behavior whose potentials are comparable to that of TTF. Good correlation was obtained between the oxidation potentials and the HOMO energies calculated by the PM3 method. A number of CT complexes prepared were classified into three groups, neutral, ionic, and non-V-shape groups. Among them, the non-V-shape group complexes contained highly conducting complexes including molecular metals. Most of the CT salts with inorganic anions having high conductivities showed lower electronic transition energies than 0.5 eV.

In order to study tritium migration processes in solid breeding materials, in situ tritium release experiments (TTTEx) using the research reactor “YAYOI” at the University of Tokyo have been performed. Polycrystalline powders or pellets of Li 2 O and LiAlO 2 were tested. By using various compositions of sweep gas (He, He + H 2 (100 ppm-1%), He + H 2 O (3–200 Pa)), primarily surface reactions were studied. The surface tritium inventory was found to decrease with an increase of H 2 pressure or water vapor pressure in the sweep gas. The pressure dependence and effects of smear density were studied. Experimental results show that tritium release from the surface is enhanced by exchange and/or recombination reactions on the surface. The mechanism of the surface reaction was investigated by combining a modeling study and out-of-pile experiments, such as adsorption and exchange reactions.

A partially deuterated κ -(BEDT-TTF) 2 Cu[N(CN) 2 ]Br salt, which is a superconductor situated near the Mott insulator, has been investigated by resistivity measurements under magnetic fields. The superconducting transition of this salt is replaced by the first-order metal–insulator transition by magnetic field. This field-induced transition fades away when the sample cooling around 80 K is slowed down. The present findings lead us to bring to mind possible realization of the ideal electric switch controllable with the magnetic field.

The phase diagram of κ-(BEDT-TTF) 2 Cu[N(CN) 2 ]Br around the metal–insulator (MI) boundary controlled by partially deuteration and by cooling rate through the 80 K anomaly has been investigated by resistivity measurements under magnetic fields. The humps of resistance were observed at 33.5 K corresponding to the T * anomaly and at 9.5 K with the hysteresis of resistance in the partially deuterated sample for slowly cooled. According to approach to the critical region of MI transition from the metallic side by the increase of cooling rate: (a) the hump of resistance at the T * anomaly is shifted towards a lower temperature and (b) the temperature of the resistance hump with the hysteresis increases. Our results suggest that these anomalies are related to the phase separation of the metallic and insulator phase around the MI boundary.

Using partially deuterized BEDT-TTF molecules, we performed 13 C-NMR study of a series of partially deuterized K-(BEDT-TTF) 2 Cu[N(CN) 2 ]Br salts, where BEDT-TTF is bis-(ethylenedithio)tetrathiafulvalene. We synthesized partially deuterized BEDT-TTF molecules 13 C-enriched on only one side of the central carbon sites. The substitution of one side of the central carbon avoid the Pake doublet and we can estimate the density of states from the Knight-shift and the spin-lattice relaxation rate. The reduced mass effect predicted from the specific heat measurement near the SC-AF1 boundary was not observed in the 13 C- NMR measurement but the phase separation behavior was observed.

The title compound undergoes a neutral-ionic (N-I) phase transition under pressure. In order to examine the electronic state of BEDT-TTF and Cl,MeTCNQ molecules separately by NMR, we prepared the complex with Cl,MeTCNQ and C, deuterium-substituted BEDT-TTF molecules. The 13 C and 1 H NMR measurements were performed at ambient and applied pressures. Under 8 kbar, the N-I transition was found to be continuous. We also found that the I-phase is nonmagnetic state.

In κ-(BEDT-TTF) 2 X, the relationship between the AF-fluctuation and the superconductivity has been discussed by many researchers. In order to investigate the mechanism of the superconductivity in κ-(BEDT-TTF) 2 X, we prepared the alloy of K-(BEDT-TTF) 2(1-X) (BEDSe-TTF) 2X Cu[N(CN) 2 ]Br and measured the magnetic properties of the alloy. The increase of X shifted T c lower and the superconductivity was suppressed over X=0.33. To check the magnetic fluctuation, we also measured the spin-lattice relaxation rate (T 1 T) -1 of the series of the alloy system.

Raman studies of α-(BEDT-TTF) 2 I 3 [BEDT-TTF is bis-ethylenedithiolo(tetrathiafulvalene)] have been performed to investigate the charge distribution between BEDT-TTFs below and above the metal-insulator phase transition at T M-1 =135 K. Following the crystal-symmetry lowering at T M-1 , clear ±0.3e deviation from average 0.5e charge has been found in the nonmagnetic insulating phase. In the paramagnetic semi-metal-like phase, the split of one of the Raman active mode suggests charge nonequivalence between donors.

κ-(BEDT-TTF) 2 X system is well known as the strong correlated electron system with the phase boundary of the superconducting and the antiferromagnetic ordering phases. We controlled the boundary with the partial deuterization technique on κ-(BEDT-TTF) 2 Cu[N(CN) 2 ]Br and found the boundary was sensitive to cooling rate around at 80 K, at which the lattice anomaly occurred. We also found the external magnetic field dependence of the boundary.

The κ -(BEDT-TTF) 2 Cu[N(CN) 2 ]Br salts were synthesized from nondeuterated, partially, and fully deuterated BEDT-TTF molecules. The electrical resistance of these salts was examined systematically as functions of temperature and cooling rate, and found to change from metallic to insulating behaviors by the progressive deuterations and increasing the cooling rate. This means the active control of the correlation effect of electrons in this family.

The κ-(BEDT-TTF)2Cu[N(CN)2]Br is a quasi-two-dimensional superconductor with the highest Tc of ∼12 K among organic conductors. However, the antiferromagnetic insulating state appears by deuteration of BEDT-TTF (κ-d8-Br) or substitution of Cl (κ-Cl) for Br. The 13 C NMR measurements of these two insulating compounds, which are situated near the superconducting phase, were carried out to probe magnetic structure. The NMR spectra of κ-Cl and κ-d8-Br clearly indicate the commensurate antiferromagnetic structure with ordered moments of 0.45μB/(BEDT-TTF)2 and 0.3μB/(BEDT-TTF)2, respectively, which provides unambiguous evidence that κ-Cl and κ-d8-Br are Mott insulators.

The compound mentioned in the title is a quasi-two-dimensional organic conductor exhibits a metal–insulator transition accompanied by structural modification at T MI ∼190 K , while the tight-binding band calculation suggests a 3/4 filled band at higher temperatures. The 13 C NMR measurements have been performed on a single crystal to clarify the electronic nature of the metal–insulator transition. At room temperature, the 13 C NMR spectrum indicates that all BEDT-TTF molecules are electronically equivalent. Below TMI, however, it splits into two kinds of spectra with different Knight shifts and spin-lattice relaxation rates. These results show that charge disproportionation occurs below TMI and that long-range Coulomb interaction is important in this system.

Thermodynamic studies for a series of partially deuterated κ -(BEDT-TTF) 2 Cu[N(CN) 2 ]Br single crystals were performed in order to see variation of the normal-state density of sates around the two-dimensional Mott transition caused by the bandwidth control. The electronic specific heat coefficient γ was found to decrease monotonously when the system approaches the boundary from the metallic region. The Brinkman–Rice-type mass enhancement is absent near the critical boundary.

A single crystal of α′-(BEDT-TTF) 2 IAuBr was synthesized and the crystal structure was determined by X-ray analysis. The structure was found to be isostructural to α′-(BEDT-TTF) 2 AuBr 2 , having the characteristics of α′-type salts in that the donor molecules are stacked to form a dimerized chain. The electronic structure of α′-type salts was proved to be one-dimensional along the stacking direction from the analysis of the polarized reflectance spectra obtained by use of the microspectroscopic technique.

The radical salts of NiPc, PtPc, and NiTBP were prepared by the method of electrochemical oxidation. The radical salts of NiPc and PtPc have 2:1 chemical composition and are metallic, the crystal structure being composed of tetragonally packed molecular columns with the metal-over-metal stacking mode. On the other hand, the radical salts of NiTBP with tetrahedral and octahedral counter anions have 3:2 chemical composition and are semiconductive, the crystal structure being composed of hexagonally packed molecular columns including a periodic unit of NiTBP trimer. All these materials have predominantly oxidized macrocycles, a small on-site Coulomb energy, and a small electron-phonon interaction.

Highly conducting materials of (phthalocyanato)nickel hexafluoroarsenate, (NiPc) 2 AsF 6 , and hexafluoroantimonate, (NiPc) 2 SbF 6 , were prepared by the use of an electrochemical technique. The crystal structures resemble that of NiPc(I 3 ) 0.33 , which is composed of NiPc molecular columns encompassed by triiode anions. The electrical conductivity of these salts exhibits a metallic behavior at least down to 200 K. It was concluded from the ESR experiment that (NiPc) 2 SbF 6 is a doubly mixed valence compound.

A single crystal of s″-(BEDT-TTF) 2 ICl 2 was synthesized electrochemically, and the crystal structure was determined by X-ray analysis. This s″-type crystal was characterized by means of the electrical resistivity, electron spin resonance, X-ray diffraction, and polarized reflectance spectrum. The temperature dependence of the electrical resistivity which was proportional to T down to 10 K shows a typical metallic behavior. The ESR spectrum exhibited a Dysonian line-shape. The intensity of the spin susceptibility abruptly decreased at 17 K, although the electrical resistivity and the Bragg diffraction intensity showed no discontinuous change: this indicates the occurrence of a magnetic phase transition. The reflectance spectrum for the //c polarization showed a Drude-like dispersion already at room temperature. The anisotropic two-dimensional electronic structure was examined by the reflectance spectrum analysis.

Semiconductive (BEDT-TTF) 2 (IBr 2 ) 2 (TCE) 0.5 salt, which is isostructural to e-I 3 , changes to metallic ones with the loss of their weight when tempered under reduced pressure. The metallic behavior retains down to 0.5 K.

3,10-Dithiaperylene (DTPR, 1a ), 1,6-dithiapyrene (DTPY, 2a ), and their dephenyl derivatives, Ph2DTPR ( 1b ) and Ph2DTPY ( 2b ), and ethylenedithiolo derivative (ETDTPY, 3 ) were prepared as examples of molecular design for condensed type donors with two sulfur atoms. They are termed peri-condensed Weitz-type donors. The electrochemistry indicates that these heterocycles are actually two-stage redox systems with low oxidation potentials, indicating large enhancement of the donor ability. We obtained relatively high conductive CT complexes utilizing these donors and TCNQ-type acceptors. Interestingly, Ph2DTPR-DDQ0.75 shows the high conductivity (compressed pellet, δ = 0.5 Scm−1) despite the fact that the complex consists of neither TTF-type donor nor TCNQ-type acceptor. In addition, ETDTPY gave highly conducting iodine complex (single crystal, 42 Scm−1). The crystal structures of Ph2DTPR, Ph2DTPR-ClO4, DTPY, and (Ph2DTPY)2I3 show columnar stacks of donor molecules.

(BEDT-TTF)2Cu(NCS)2 was found to be the first ambient pressure organic superconductor with the Tc higher than 10 K. The salt has a layered structure which is composed of donor and anion sheets. The packing pattern of donors of the Cu(NCS)2 salt is nearly analogous to κ-(BEDT-TTF)2I3. In anion layers CuI is trigonal coordinated to two N atoms and one S atom to construct a one-dimensional planar polymer. The valence state of CuI was observed by ESCA at 298 K and ESR at 298-4 K. One broad Lorentzian ESR signal ascribed to a BEDT-TTF cation radical was obtained. The g-values are independent of temperature, while the linewidth shows broadening with lowering temperature even though the resistivity decreases below 90 K. The ESR magnetic susceptibility is constant down to 90 K, which is suggesting Pauli-like paramagnetism. The thermopower is anisotropic in the two-dimensional bc plane, which is originated from the anisotropy of the band structure.

In-situ tritium release experiments were performed for γ-LiAlO2 polycrystalline powder (5–9, 6–7, 9–16, 10–14 mesh) and pellets (8 mm diameter × 10 mm high) with three bulk densities of 55% T.D., 78% T.D. and 90% T.D. at 470–780 °C using sweep gas of He+10; 100; 1000; 10000; 30000 ppm H2. The particle size dependence of tritium residence time in the sample was measured using sweep gas of He+10000 ppm H2. The experimental results were analyzed using a two-step diffusion model. Tritium diffusivities in grain (Dg) and for intergrain (Dint) were separately evaluated. The value of Dg was Dg[cm2/s] = 1.82 × 10−7 exp(−84.5[kJ/mol]/RT), and Dint was found to have a strong correlation with the bulk density. The tritium residence time decreased with the increase of H2 concentration in the sweep gas. The major part of the released tritium was the water-forming component in the regime below 1000 ppm H2, while the non-water-forming component was dominant in the regime above 10000 ppm H2.