Thin films of rare earth sulfides were prepared for the purpose of obtaining materials with enhanced variation of the electrical conductivity against the sulfur pressure and also with faster response to the atmosphere. Cerium iaad erbium were employed as rare earth ele7meats. In the cerium sulfide thin film, the electrical conductivity (σ) decreased with increasing H₂ content in H₂S/H₂ gas mixture (Fig.4). The relationship σ∝P_S2^1/6 was obtained over the temperature range from 873 to 1073 K (Fig.6); this indicates the establishment of the following equilibrium reaction.
1/2 S₂⇔S_s + V_Co'' + 2h·
In the case of the erbium sulfide thin film, the conductivity depends only on the sulfur pressure at temperatures between 873 and 1173 K (Fig.7). The slope of log σ against log P_S2 is close to 1/4, suggestive of the following equilibrium:
1/2 S₂⇔S_s + V_Er' + h·

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Several kinds of carbon fibers were heat-treated at temperatures over 3000°C and intercalated with AsF₅, and their properties were studied. The electrical conductivity of vaporgrown carbon fibers prepared from benzene, increased by one order of magnitude by the hightemperature treatment and became comparable to those of highly-oriented pyrolytic graphite (HOPG) and natural graphite. Furthermore, graphite compounds with very high electrical conductivity were produced by the successive intercalation of AsF₅. High electrical conductivities above 1×10⁵ Sicm were reproducibly obtained by the high-temperature treatment and AsF₅-intercalation to the vapor grown carbon fibers. The AsF₅-intercalated vapor grow n graphite fibers were relatively stable in air. It was found that AsF₅ predominantly entered to the fibers from their ends.

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The relationship between the thdrmoluminescence (TL) and the electrical conductivity was investigated on the binary sulfate crystals which were prepared by blending various alkali metal sulfates with Ag₂SO₄. When the cationic radius of the sulfate blended with Ag₂SO₄ was smaller or larger than that of Ag₂SO₄, the TL intensity on the binary sulfate crystal was low or high, respectively. A maximum TL value was observed with the Rb₂SO₄-Ag₂SO₄ system. The electrical conductivity was lower in the Rb₂SO₄-Ag₂SO₄ system which does not form a solid solution than in the Na₂SO₄-Ag₂SO₄ system which forms a solid solution. Thus, the high TL intensity of the Rb₂SO₄-Ag₂SO₄ system, suggesting the higher stability of the emitting center therein, could be correlated with the low bulk conductivity of this binary sulfate crystal.

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Transparent Conductive IrO_x films have been prepared by reactive sputtering of a iridium target in the atmosphere of oxygen. The IrO_x is p-type conductor while existing transparent conductors, such as In₂O₃, SnO₂, and ZnO, are n-type. Due to this marked feature, IrO_x may be applied to transparent junction layer in solar cells or photosensors, as well as an anode material in fast-response electrochromic display devices (ECD).
Typical properties of an IrO_x film of 500Å in thickness are as f ollows: transmittance 85%in the visible light, conductivity 60S·cm^-1 at room temperature, sheet resistivity 300Ω. Optical, electrical and electrochromical properties of IrO_x films prepared under various sputtering conditions are described. Bonding structure and valence band profiles are investigated by the measurements of X-ray photoemission spectroscopy. Properties of IrO_x films are discussed on the basis of an electronic state model for IrO_x by taking account of nonstoichiometory.

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Transparent conductive films of indium tin oxide (ITO) were deposited by reactive sputtering using a d. c. planar magnetron cathode. The deposition rate, Rd, is determined by the competitive reaction between sputtering and oxidation on the target surface. As-deposited films are all amorphous state which is classified into four phases as a function of increasing Rd; oxide (A-I, A-II), reduced (B-II) and metal-rich (B-III) phases. The films prepared at the lower Rd(A-I or A-II) are oxidized progressively by annealing in air and the resistivity increases, yet the structure remains amorphous state. On the other hand, the films prepared at the higher Rd (B-II, B-III) are at the same time oxidized and crystallized progressively by annealing in air and the resistivity decreases.
The relations between the characteristics of the film and the sputtering conditions, such as the substrate temperature or/and concentration of tin, are also discussed.

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The highly-doped semiconductor has been demonstrated to be an excellent conductive material as an electrode for the analysis of an electron-transfer process at an electrode/solution interface quantitatively. That is to say, the measurement of the current flowing through the space charge layer of the semiconductor by the tunneling effect in this electrode system enables us to obtain the kinetic parameters of. the electron-transfer reaction experimentaly. The authors formulated the tunnel cathodic current as a function of the electrode potential for outer sphere redox species. In this paper, the utility of the electrode for measuring the solvent rearrangement energy (λ) in the Marcus-Gerischer theory was precisely presented.
In practice, the values of λ of the electron-transfer reactions for some ions in aqueous solution were measured by use of the electrodes. The current-potential characteristics at the electrode obtained by the potential linear sweep method, as shown in Fig.1, indicated that the current was limited by the charge-transfer rate at the interface and λ was obtained directly by use of Eq. (11) from the slope of α-V curves such as Fig.6, where α is the transfer coefficient. In contrast, λ could not be even estimated from i-V curves at Pt nor ordinary doped TiO₂ electrodes.
The results of the measurement of λ were tabulated in Table 1. These measured values of λ were independent of the semiconductors used as the electrodes, i. e. tin oxide and indium oxide. And λ was very sensitive to the change in the structure of ions. For example, λ of Fe³⁺/Fe²⁺ in 1 mol/dm³ HClO₄ was 0.30 eV, which corresponded to λ of [Fe(H₂O)₆]^3+/2+, while λ of Fe³⁺/Fe²⁺ in 3 mol/dm³ H₂SO₄ was O.36 eV, which corresponded to λ of [Fe(SO₄)₂(H₂O)₂]^-/2-. The results in this work suggested that the Born's equation had overe stimated the value of λ as indicated in Table 2.

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Several disubstituted derivatives of 11, 11, 12, 12-tetracyanoanthraquinodimethan(TCNAQ)were prepared, and substituent effects on their reduction potentials and semiquinone formation constants K_sem were studied. The substituent effects on TCNAQs are quite small comparec with that of 7, 7, 8, 8-tetracyanoquinodimethan(TCNQ), attributable to the nonplanar structures of TCNAQ derivatives. In spite of severely deformed structures, the TCNAQ derivatives favorably gave molecular complexes with various donors, in which the mole ratio of the complexes mainly depends on the steric requirements in crystal lattice. In order to remove the steric interaction between dicyanomethylene groups and pen-hydrogen atoms, bis (1, 2, 5-thiadiazolo) tetracyanoquinodimethan (BTDA-TCNQ) and (1, 2, 5-thiadiazolo) tetracyanonaphthoquinodimethan (TDA-TCNNQ) were prepared. BTDA-TCNQ was found ta form a highly-conductive complex with tetrathiatetracene(TTT), and its anion radical salts were isolated as stable form. On the contrary, the reduction potentials and K_sem of TDA-TCNNQ show that its anion radical is not thermodynamically stable, suggesting that thsteric hindrance still exists in TDA-TCNNQ.

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Stackings of TTF (tetrathiafulvalene) and related donor radical cations (and molecules) in the salts seem to be greatly influenced by the geometry and the formal charge of counter anions. Of metal halide anions, fluorosilicate ions are of interest partly because of their small sizes. TTF, TSF (tetraselenafulvalene), and DBTTF (dibenzotetrathiafulvalene) were electrochemically oxidized in an acetonitrile, dichloromethane, or benzonitrile solution of [NPrⁿ₄] [SiRF₄] (R-=-F, Me or Ph) or Na₂SiF₆ as a supporting electrolyte to afford salts with the [SiF₅]- or [SiF₆]^2- ion; [TTF]_1.6[SiF₅], [TTF]_2.7[SiF₅], [TTF]₃[SiF₆], [TSF]₃[SiF₆], and [DBTTF]₂[SiF₅]. Powder reflectance spectra of the salts show a band due to dimeric (D⁺)₂ (D=donor molecules) in the 12400-45200 cm^-1 region, as well as a band due to a D⁺/D⁰ charge-transfer transition in the 8600-9000 cm^-1 region. The [SiF₅]^- ion interacts with the TTF columns through the silicon-sulfur coordination, while it exists as a penta coordinate anion without silicon-sulfur interactibn in its DBTTF salt. All the salts behave as typical semiconductors with the electrical resistivities in the or der 1×(10⁰-10⁴)ω·cm as compacted pellets at 25°C.

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Two types of N-docosylpyridinium TCNQ [1] monolayers having different area-per-molecule values were prepared by regulating the subphase temperature at 4°C and 17'C. These monolayers were deposited on a glass slide as Y-type films at 3-5°C and 17°C (abbreviated as Low-temp. and High-temp. films, respectively).
Measurements of electronic spectra s howed that the long axis of the TCNQ redical anion is parallel to the substrate plane in the Low-temp. film, whereas it is tilted with respect to the substrate plane in the High-temp. film. These results indicate that the specific orientation of [1] on the air-water interface is preserved in each case even after the deposition onto the substrate.
The conductivity of the High-temp. film along the plane was ca.5x10^-5S·cm^-1, which is about 10² times larger than that of the Low-temp. film this reflects the difference in orientation and overlapping of the TCNQ molecular planes.
The process described above provides a new possibi tity of controlling the donor-acceptor orientation in charge-transfer complexes by means of the Langmuir-Blodgett techinique.

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Soliton behavior on trans-polyacetylene were investigated from a chemical point of view. It was recognized that solitons act as a kind of mobile free radicals, which were selectively reduced by the gas phase reaction with ρ-thiocresol. The selective soliton reduction was confirmed by ESR and infrared absorption spectroscopy.
The soliton reduction effect on polyacetylen e was measured by the changes in the electrical conductance and the infrared absorption spectra during the oxidation. When the concentration of neutral solitons was reduced to one-third, the oxidation rate constant k was decreased by one-fourth without any changes in the oxidation mechanism. The oxidative reaction obeyed the pseudo first-order kinetics and its activation energy, E_a, was 13.5 kcal/mol. The soliton reduction did not largely influence the electrical conductivity. In the oxidation reaction, the electrical conductivity changes in the soliton reduced polyacetylene were less than those in the normal trans-polyacetylene.

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Ion implantation has been applied to polyacetylene, (CH)_x, films in order to develop a stable n-type doping technique. According to the analysis based on the LSS theory, the transition energies at which nuclear and electronic stoppings become equal in (CH)_x are 6, 65, and 194keV for Li⁺, Na⁺, and K⁺, respectively. Concentration profiles of these implants at a given energy and dose are also calculated using the corresponding projected range and its straggling predicted from the LSS treatment.
Ion implantation doping of high-density(CH)_x films was demonstrated with Na⁺ in a relatively low-energy region where nuclear stopping is a dominant process. The surface took on a metallic luster after implantation. The sample did not show any signs of carbonization or sputtering. The sheet resistance of the film implanted with 6 keV Na⁺ to a dose of 6×10¹⁶ cm^-2 was by about three orders of magnitude lower than the original value. The change in the resistivity of the implanted layer should extend over about seven orders of magnitude, since the projected range of Na⁺ was only 0.01% of the total film thickness.
A p-n junction formed in the film by ion implantation exhibited a diode characteristic for over 600 h, in contrast to the poor stability of a junction prepared by chemical or electrochemical doping.
Suppressi on effects on diffusion of dopant species are characteristic of the ion implantation.

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Characterization and electrical properties of undoped cis-polyacetylene and annealed polyacetylene were studied by measuring the electrical conductivities, the rate of isomerization, the cis-trans content, wide angle X-ray diffraction (WAXD) and electron spin resonance (ESR). In cis-polyacetylene the electrical conductivity decreased with a decrease in the amount of residual catalysts. The electrical conductivity decrease with excess heating since the interchain cross-linking of the radicals was occurred, which also induced a decrease of crystallinity. The activation energy of cis-trans isomerization increased with an increase in the trans content. The crystal transition during the isomerization occurred following a certain amount of cis-trans isomerization in the polyacetylene chain. Two crystal structures were found in trans-polyacetylene.

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1, 6-Dibromo-2, 4-hexadiyne has been polymerized in a vacuum by heating, resulting in the formation of a conjugated polymer. The polymer is soluble in dimethyl sulfoxide (DMSO) and tetrahydrofuran (THF), and can be formed into thin films. Its molecular weight is estimated at 25000 by gel permeation chromatography (GPC). The polymer is an acceptor and makes change-transfer (C-T) complexes with donors such as ammonia and tetrathiafulvalene (TTF). Consequently, its conductivity increases to 10^-1S·cm^-1, as shown in Table 1 and 2. Acceptor molecules such as iodine and tetracyanoquinodimethan (TCNQ), however, don't cause the conductivity to increase very much (up to 10^-6-10^-7S·cm^-1). That is quite different from the property of the usual conducting polymers such as polyacetylene. The single crystal of poly(2, 4-hexadiyne-1, 6-diyl ditosylate) and the pellet of the cross-linked polyester made from 2, 4-hexadiyne-1, 6-diol and adipoyl dichloride also form the C-T complexes with ammonia, their conductivities being raised up to 10^-4-10^-6S·cm^-1, as shown in Fig.5. The electron-withdrawing abilities of these poly(diacetylene)s depend on their resonance structure shown in Equation (2): the positive charge exists on their polymer backbones, and the negative one on their substituents. The strength of poly(diacetylene) as acceptor or as donor can be controlled by changing its substituent. The acceptor-donor relations among poly(diacetylene)s and dopants are proposed in Fig.6.

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As a part of our studies on preparation of electrically conducting, nonconjugated pendant polymers and their applications, electrolytic polymerization of 1-vinylpyrene, electrochemical doping of poly(1-vinylpyrene) and electrical conductivities of resulting polymers have been studied. An electrochemically doped polymer was deposited on the surface of the electrode by the controlled-potential anodic oxidation of 1-vinylpyrene in dichloromethane containing tetrabutylammonium perchlorate as the supporting electrolyte. Likewise, the controlledpotential anodic oxidation of poly(1-vinylpyrene) produced an electrochemically doped polymer. The electrochemically doped polymers thus formed are partial cation radical salts with ClO₄^- as a dopant. The room temperature conductivity of ca. 10^-7S·cm^-1 was observed for the polymer with a doping degree of 35%. Electrical conductivities under pressures of 120 kg·cm^-2 and 2900 kg·cm^-2 were found to increase by a factor of one or two orders of magnitude, respectively, and the conductivity changes with a pressure were reversible.

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Poly(1, 4-dithianaphthalene) (abbreviated to PDTN), and polyphenylene sulfide (poly(thio1, 4-phenylene), abbreviated to PPS) shown in Fig.1 have been treated with electron acceptors (Br₂, SbCl₅) to form moderately conducting complexes with electric conductivities up to 10^-3S·cm^-1 as summarized in Table 1. In order to discuss the transporting mechanism of the polymers, measurements of electron spin resonance and static magnetic susceptibility were carried out with powder samples. The principal values of the g-tensor observed for the radicals were typically 2.0134, 2.0072, and 2.0025 with the average g-value being 2.008 as summarized in Table 2. From these results, it is suggested that the unpaired electrons in the polymers are delocalized on the linking-sulfur and phenyl-carbon atoms. The number of the unpaired electrons estimated from the Curie constant, which was obtained by the static susceptibility measurements, was found to be less than one-tenth of the number of the dopant. This discrepancy is interpreted in terms of the bipolaron formation as illustrated in Fig.8.

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Changes in electrical properties and the structures of poly(metal-yne)s, that is, poly(butadiynylcopper) (Cu⁺Bdy) and poly(butadiynylenecopper) (Cu²⁺Bdy) (Fig.2) upon iodine doping, have been investigated. With an increase in iodine uptake, the conductivity of Cu⁺Bdy increased rapidly and reached the saturation level of 6.3 S/cm at the dopant concentration of y=∼0.1, On the other hand, the conductivity of Cu²⁺Bdy increased gradually and reached 10.2 S/cm at y=∼O.3 (Fig.3). SEM and XMA observations revealed that the dopant distribution in Cu¹⁺Bdy at the saturation level of conductivity increase was qu ite heterogeneous through the cross section of pelletized specimen (i. e. only near the surface), while it was homogeneous in Cu²⁺Bdy (Fig.5). The real molar ratios of iodine to poly (metal-yne)s in the doped area at the saturation level were almost the same between Cu⁺Bdy and Cu²⁺Bdy, and were 0.25-0.3 iodine atom (i. e, ∼0.1 I₃^- ion) for repeating unit.
ESR measurment showed the existence of locallized unpaired electron (Fig.6 and Fig.7). With iodine uptake, the amount of electron gradually decreased, resulting in the formation of Dysonian-shaped metallic electron (Fig.8). This result conforms well to the previous observation that the conductivity dose not change at all down to 7 K. XPS measurment suggested that the back donation of π-electron from acetylenic moiety to the metal ion was effective in both undoped poly(metal-yne)s, and verifyed no significant changes in the bond between copper and carbon before and after the iodine doping. WAXD (Fig.9) revealed no existence of CuI in doped poly(metal-yne)s.
Based on these results, a conduction mechanism has been proposed (Fig.10).

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The electrochemical polymerization of pyrrole on the electrode. coated with poly(vinyl chloride) (PVC) film produces electrically conductive polymer alloy films of the PVC and polypyrrole. The polymerization of pyrrole is initiated at the interface between PVC films and electrode, and then polypyrrole grows inside the PVC films. At the early stage of polymerization, only the electrode side of the film becomes conductive and the surface side of the film is completely insulating. The surface side becomes conductive, when the amount of polypyrrole incorporated in the PVC film is so much that polypyrrole chains reach to the surface side of PVC film.
The electrical resis tance and light transmittance of PVC/polypyrrole alloy films can be widely controlled by the polymerization conditions, particularly the applied voltage and the charge density, that is proportional to the quantity of polymerized pyrrole. Highly conductive polymer alloy film, of which surface resisitance is less than 200 Ω can be obtained with 20 μm-thick PVC film. When the amount of polypyrrole in the PVC film is limited, semitransparent conductive films with a transmittance of 60% and a surface resistance 1.7-4.2 kΩ (conductivity: 2-5/Ωcm) can be realized in a free standing form.

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Highly conductive polypyrrole films doped with ρ-toluenesulfonate have been prepared by the electrochemical method and their properties as the shielding material for the electromagnetic wave have been studied in detail. They have been especially effective for shielding electric fields and the attenuation higher than 30 db has baen obtained in the frequency range between 3 and 300 MHz with a film of 50 μm in thickness. However, the effect of magnetic shielding has been not so remarkable (less than 10 db). These results are consistent with the ordinary theory about the attenuation of an electromagnetic wave passing through a conducting material.

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Transparent and conducting composite films of polypyrrole have been prepared by exposing polymeric films containing iron (III) chloride to pyrrole vapor. The conductivity and transmittance of composite films were 10^-2-5×10^-1S·cm^-1 and 80-95% respectively, when poly(vinyl alcohol) was used as a polymeric matrix. The conductivity and transparency depended on polymerization time, temperature and FeCl₃ concentration considerably. In forming highly transparent and conducting composite films, the optimum conditions of FeC13 concentration and polymerization time were 5 wt% and 24 h or 30 wt% and 30 min. The absorption of the polypyrrole-PVA composites was not in proportion to weight % of polypyrrole in the composites. Therefore, it was suggested that the carrier densities and mobilities in each of polypyrrole composite films were different. The composite films of the high transparency as well as fairly good conductivity were obtained when the high mobility was attained rather than the carrier density. By the observation of scanning electron micrographs, the surface morphology of polypyrrole-PMMA composite films was cleared. It was found that the temperature dependence of the conductivity and thermopower of composite films prepared by this method were similar to those of polypyrrole by electrochemical polymerization.

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Effect of doping on the conductivity was investigated with poly(4-phenyl-1, 2, 4-triazole3, 5-diyl)-[m-, ρ-and m-/ρ-phenylene] ([1], [2] and [3]) and poly(1, 2, 4-triazole-3, 5-diyl)[ρ-phenylene] [4]. These polymers were doped with electron acceptors such as iodine, bromine, sulfur trioxide, antimony (V) fluoride, iron(III) chloride, phosphorus pentachloride and titanium (IV) chloride. The electrical conductivity of the doped polymers increased up to the order of 10^-3 S/cm. The conductivity of [1] doped with iodine was proportional to the fourth power of the dopant content. Although [1] is soluble only in sulfuric acid and formic acid, and [2] only in sulfuric acid, they become soluble in acetone and nitromethane by the addition of iodine and iron (III) chloride, respectively, and can be fabricated into tough films by casting technique. The analyses of infrared spectra, Raman spectra, UV-VIS spectra and NMR-spectra suggested that the increase of solubility and conductivity by doping was due to the formation of charge-transfer complex between triazole ring and dopant.

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Polythienylene(PT) and poly(3-methylthienylene)(P 3 MT) films, synthesized by electrochemical polymerization of thiophene and 3-methylthiophene, have been analyzed using IR spectrometry, ¹³C-NMR and XPS(X-ray photoemission spectrometry). The samples investigated include as-grown films havily-doped, undoped ones from the as-grown films and redoped ones from the undoped films. Drastically undoped films of PT₀ and P 3 MT₀ exhibit primary absorption bands in the infrared spectrum at 789 and 819 cm^-1, respectively. These bands, due to C-H out-of-plane vibrations of 2, 5-disubstituted thiophene, indicate that these films consist of poly(2, 5-thienylene) or poly(3-methyl-2, 5-thienylene). The ¹³C-NMR analyses also support this conclusion.
The chemica l species of dopants contained in the P 3 MT films were identified by the XPS and their content was determined. The major chemical species of dopants are ClO₄^-, I₅^-ions, AsF₅ groups and BF₃ groups; their content (y) ranged from 0.0003 to 0.07 per (C₅H₄S)_0.25, in other words, the carbon atom participating in the π-conjugated system of P 3 MT. The conductivity of these P 3 MT films ranged from 10^-12 to 10² S·cm^-1 according to the dopant contents. This conductivity, together with the activation energy of conduction, varies as a function of the dopant content, being independent of the difference in chemical species of dopants. In particular, a sudden change is observed near y=0.006 in the dependence of the activation energy of the dopant content. The evidence may be associated with the semiconductor-metal transition in P 3 MT molecular chains.

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The low molecular organic compounds with the unit structure of polymer containing hetero ring in the main chain have been found to manifest semiconducting properties and the photoconducting phenomena.
The present work deals with the substituent effects on the spectral characteristics and photoconduction of a series of 3-phenyl-5-(ρ-substituted benzylidene)rhodanine. The assigned characteristic frequencies of CO streching frequencies in aromatic-substituted thiazolidine ring are located to high frequencies with increasing Hammett's σ value. The relation between the pre-exponential factor of the conductivity and the activation energy of conduction in the temperature dependence above and below kink temperature fitted well to the compensation law, respectively.
The effect of substitute of aromatic rhodanine derivatives on the photocurrent showed in the following order; N(CH₃)₂>NHCOCH₃>OCH₃>OH>CH₃ for electron-repelling groups, NO₂>Cl for electron-attracting groups. It was suggested that the major carrier of photoconduction was hole for N(CH₃)₂ and OCH₃ groups and a electron for other substituent groups on the basis of an irradiated polarity effect of an comb-shaped silver electrode. Action spectral of photocurrent is consistent with the transmitted spectrum in evaporated film.

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In order to obtain a layered-type electrophotographic photoconductor of high photosensitivity in the practical range of wavelengths, bisazo pigments having a 1, 4-distyrylbenzene moiety as the main structure unit (Fig.2) were synthesized. The bonding mode of the phenylene rings in the 1, 4-distyrylbenzene moiety was varied, and relationships between the bonding mode and the spectral absorption, and the bonding mode and spectral sensitivity were investigated (Table 2). As a result, it was found that the absorption spectra of the bisazo pigments undergo a significant blue shift as shown in Table 3 when the bisazo pigments contain o-phenylene bonds and/or m-phenylene bonds. This is because the steric hindrance effect owing to o-phenylene bonds affects the resonance in the molecule, and m-phenylene bonds insulate the conjugation in the molecule.
In bisazo pigments synthesized using Naphthol AS as a coupler, a flat keto-hydrazone structure is favored by the intramolecular hydrogen bonding of amide protons and this flat structure assists the intermolecular interaction of the bisazo pigments. This intermolecular interaction contributes appreciably to the appearance of the photoconductivity in the bisazo pigments.
The deformation of the molecular structure caused by the steric hindrance decreases the intermolecular and intramolecular hydrogen bondings. As a result, the photoconductivity is decreased (Table 5).
The effects of su bstituents of the anilide rings in the bisazo pigments on the photosensitivity were also investigated. The result is that the substituents have considerable effects of the photosensitivity of the bisazo pigments. It is considered that this is because the substituents delicately change the hydrogen-bonding state in the amide moieties.

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An application of azulenium compounds, synthesised by the condensation with 1, 4-dimethy1-7-isopropylazulene and ρ-dimethylaminocinnamaldehyde in the presence of strong acids (HClO₄, HBF₄, HBr and Hl), to a charge generation layer of a double layer organic ph otoconductor was described.
Spectral sensitivity measurements show each compound has a broad sensitivity across a wide range of wavelength. In addition, measurements of the X-ray diffraction have proved that either of the compounds is highly crystallized for all the difference of the crystal forms.
The broad spectral sensitivity is primarily due to the crystal's molecular conditions which are regularly stacked and represent a broad absorption characteristic resulting form the π-orbital interactions between molecules.
The sensitivity of each com pounds on the counter ion. Azulenium compounds with iodide counter ions have the highest sensitivity, their half decay exposure at the near-infrared spectrum of 850 nm being 0.25 μJ/cm².
Furthermore, an application of tile iodide compounds for the electrophotographic photo, conductor has been investigated. Both the color reproduction and the sensitivity to laser diodes have proved that the compounds can also be utilized for color copiers and laser printers.

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A new morphological structure of magnesium phthalocyanine (MgPc) compound has been observed when MgPc was recrystallized from a strong donative solvent such as morpholine. The aggregate structure of MgPc prepared by this method exhibited strong absorption in the infrared region (800-850 nm) and, consequently, an excellent sensitivity (incident energy required for half reduction of initial surface voltage E_1/2=3-4 ergs/cm² at 850 nm) was obtained in the MgPc-polyester dispersed type photoreceptor. The increase in the sensitivity due to a significant decrease in the induction period of the photo discharge characteristics of MgPc-polyester photoreceptor has revealed the possibility of a low-cost material available for a laser diode printing system.

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Poly(2, 5-thienylene) [1] and poly(3-methyl-2, 5-thienylene) [2] easily react with several metal halides to give dark brown or black adducts which show electric conductivities of 10^-7-10^-3 S·cm^-1 depending on the combination of the polymer and the dopant. The highest conductivity (2.0×10^-3 S·cm^-1) is obtained in the case of [2] doped with SnCl₄. Comparison of properties of various adducts reveals that amount of metal halides adsorbed to the polymer is relatively large when the metal halides having strong Lewis acidity are used and t hat adducts of the polymer with the metal halides having strong Lewis acidity show high spin concentration in the ESR spectra.

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Derivation of the anisotropic plasma frequencies of the tetramethyltetraselenafulvalene salts (TMTSF)₂X is given with taking account of the quasi-one-dimensional electronic band, the anisotropy of the core dielectric constant, and the non-orthogonality of the structural system. By applying the obtained expressions, Eqs. (16), to optical and structural data, the values of the transfer energies t_a and t_b for three (TMTSF)₂X are obtained. By using these values the SDW transitions in the (TMTSF)2X are discussed in the light of the theoretical crite rions for the existence of SDW at low temperatures.

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catena-μ-Ethynylene-phthalocyaninatocobalt(III) was synthesized by the reaction of dichlorophthalocyaninatocobalt(III) with bis(bromomagnesio)acetylene. This polymer was regarded as a novel type of an one-dimensional polymer, consisting of phthalocyanine radical species. The one-dimensional structure of this polymer was confirmed by IR spectrum and X-ray analysis. The conductivity of this polymer was found to be 3×10^-4 S/cm at room temperature without doping. This conductivity was explained by an increase of the carriers induced by the radical phthalocyanine rings.

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The photoconductive properties of a chloroform-cast film of poly[4, 6-decadiyne-1, 10-diol bis ([n-butoxycarbonyl) methyl]urethane)] [poly(3 BCMU)] were examined using a sand wichtype cell. The dark current decreased very slowly with time, while the photocurrent responded to illumination with a response time of 30-40 s. On the basis of these findings, the electrical conduction of the poly(3 BCMU) film was explained by the “trap-controlled conduction mechanism”. In the measurement at the range of wavelength λ=300-800 nm, the large photocurrent was observed at λ<500 nm, but the weak photocurrent was observed in the visible and near infrared region. Spectral dependence of the photocurrent was found to be similar to that of poly(diacetylene) single crystals reported.

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By using electron spin echo technique at room temperature, the spectrum of small amount of spins immobilized through interaction with oxygen is separated from that of mobile spins which give strong cw-ESR signal of trans-polyacetylene. The relative spin concentration, which is estimated to be 3×10^-3for nonexposed trans-(CH)_x, increases to 5×10^-3after exposure to air for 60 min. Application of electron spin echo technique for characterizing sample quality of polyacetylene is discussed.

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Superionic conducting glasses in the systems Aal-Ag₂Ch-P₂Ch₅ (Ch =O. S. Se) were prepared and their properties such as glass transition temperatures, ionic conductivities, electronic conductivities and ion transport numbers were measured. The effect of the replacement of anions, O, S and Se, on these properties and the conduction mechanism were discussed.
The glass-forming region was the widest in the sulfide system; in oxide and selenid e systems the region was smaller and similar each other in the area in the composition triangles. The glass transition temperatures ranged from 50 to 230°C and increased in the order of oxide, sulfide and selenide glasses, provided that the glasses contained the same amounts of Aal-Ag₂Ch-P₂Ch₅. The composition dependence of glass transition temperatures sugge sted the presence of partial covalency between Ag+ and nonbridging anions Ch^-. The conducitivity as high as 10^-2 S·cm^-1 at room temperatare was obtained in each system. The measurement of ion transport numbers revealed that all the glasses obtained were nearly 100% Ag⁺ ion conductors. The electron conductivity was less by 5 to 7 orders of magnitude than the total conductivity. The diffusion path model was concluded to be a more reasonable mechanism of conduction than the random site or the weak electrolyte model.

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The correlation between ionic conductivity and segmental motion was investigated in the polymer complexes consisting of crosslinked poly(propylene oxide) (PPO) and lithium perchlorate (LiClO₄) in a rubbery state. The ionic conductivity was the order of 10^-6 S·cm^-1at 40°C. The conductivity vs. LiClO₄ concentration curves took a maximum at a certain temperature. The main charge carrier was Li⁺ ion, whereas ClO₄^- ion also contributed somewhat to the ionic conductivity. The temperature dependence of the ionic conductivity followed the Williams-Landel-Ferry (WLF) type equation. The temperature dependence of the dielectric relaxation time, which corresponds to the micro Brownian motion of the PPO main chain, also followed the WLF equation. The comparison between the temperature dependences of the ionic conductivity and the dielectric relaxation time suggested that the migration of Li⁺ ion was closely correlated to the segmental motion of the PPO chain. The dissociated Li⁺ ion might be associated with the PPO main chain, and the segmental motion of the PPO chain with Li⁺ ion might cause the ionic migration.

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A new type of amperometric gas sensor using a proton conductor (antimonic acid) is developed for detecting small amounts of H₂ (or CO) in air at ordinary temperature. The sensor element was composed of the following electrochemical cell (Fig.1): (counter electrode) air, platinum black proton conductor' platinum black, sample gas (sensing electorode). This sensor exhibited fast response at room temperature, e. g., 90% response time for 2000 ppm H₂ was as short as about 10_s (Fig.3). The short circuit current of the sensor was found to be in direct proportion to the H₂ concentration (Fig.4), while the response (EMF) of the previous potentiometric one was almost proportional to the logarithm of H2 concentration (Fig.2).
The sensing mechanism of this sensor was shown to be attributed to the migration of the H⁺ produced by the reaction (H₂→2H⁺+2e) on the sensing electrode through the prto n conductoarn dt he consumptiofn the H⁺ accorditnog the reactio (1/2O₂ + 2H⁺+ 2e→H₂O) on the counter- and the sensing-electrode (Figs.5 and 9). This mechanism was verified experimentally by measuring the actual polarization curves for the above two reactions (Fig.6) and by observing the behaviors of the respective electrode potential under both open and short circuit conditions (Fig.8).
Furthermore, the sensor could be modified into a simpler construction (Fig.1) which eliminated the reference gas (air). This modified sensor was found to exhibit performance for H₂ detection as good as that of the original one (Fig.11). The possible sensing mechanism of this sensor was also proposed for detection of H₂ (Fig.12). The sensor was shown to be sensitive to small amounts of CO (ca.100 ppm) in air (Fig.13), while it was insensitive to methane (15000 ppm) and propane (7000 ppm) in air.

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The ionic conductivities of the hybrid films composed of poly [oligo(oxyethylene)methacrylate] and alkali metal thiocyanates were measured. Contrary to the order of ionic radius, the hybrid films dispersed with KSCN showed the higher ionic conductivity (σ=3.3×10^-5 S/cm, 25°C) than those of other systems, because of the smaller dissociation energy of KSCN than NaSCN or LiSCN. The difference in the ionic conductivity of these films depends on the numbers of carrier ions. The ionic conductivity is, however, changed by the maximum value with an increase in the salt concentration, because the conductivity also depends on the micro viscosity of the hybrid films. The conductivity was revealed to be related to the T_g of the hybrid films.

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Thin films of the V₂O₅-WO₃ system with various compositions were prepared by a reactive sputtering technique in hydrogen-argon plasma. All the films obtained were amorphous and were exhibited mixed conduction of ion and electron. The chemical diffusion coefficient D of lithium in these films increased with increasing W0₃ content, W/(W+V), up to 0.63. Its value in the range between 0.63 and 1 of the tungsten content was almost constant, about 10^-15 m²/s (25°C), while D for a pure V₂O₅ films was 10^-17 m²/s. The charge-discharge characteristics of these thin film cathodes were investigated using a solid state lithium cell with Li_3.6Si_0.6 P_0.4O₄ solid electrolyte. Of the composition investigated, the capacity loss during cycles was minimum for a WO₃ thin film. The 55% of its initial capacity was lost in the first 100 th cycles, but no more loss was observed up to 400 th cycles after that.

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A polypyrrole-coated electrode was used together with a platinum electrode in order to control pH of an aqueous solution electrochemically. It was ascertained that electrochemical doping and undoping reactions, i. e. incorporation and release of supporting electrolyte ions, on the polypyrrole-coated electrode do not change the pH of a solution significantly. On the other hand, hydrogen and oxygen evolution reactions on a platinum electrode are well-known to change the pH of a solution. When these two electrodes, which we named “pH modulator”, were used together, the pH of a solution could be changed swiftly. For example, the pH was changed between 5 and 9 many times. When the electrochemical doping and undoping reactions of organic conducting polymers are used in aqueous solutions, those polymers must have their doping and undoping capacities in a certain voltage region between the voltages where hydrogen and oxygen evolution reactions occur. Cyclic voltammetric examinations proved that a polypyrrole-coated electrode has its doping capacity in the voltage region. The doping capacity was found to be proportional to the amount of polypyrrole deposited on the substrate electrode. Compared with other organic conducting polymers, polypyrrole was found to be the best organic conducting polymer for the pH modulator use.

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Electron-transfer mediation and catalysis of electroactive polyaniline(PA)-coated basal plane pyrolytic graphite(BPG) electrodes, which were prepared by electropolymerization of aniline in an acidic aqueous solution, for the oxidation or reduction of solution-phase redox species (i. e., Fe³⁺, [Fe(CN)₆]^4-, [Fe(CN)₆]^3- and [W(CN)₈]^4-) were examined by cyclic voltammetry, normal pulse voltammetry and hydrodynamic voltammetry using rotating disk electrodes.
The electrode reaction of Fe^3+/2+ couple at PA-coated BPG electrode was found to be much faster than that at uncoated BPG electrode, reflecting the fact that the standard rate constant of the electrode reaction of PA film on BPG electrode is about ten times larger than that of Fe^3+/2+ couple at uncoated BPG electrode. From the dependence of the limiting current of hydrodynamic voltammograms for the reduction of Fe³⁺ ion at uncoated and PA-coated rotating disk BPG electrodes upon the rotation rate of electrode, the concentration of Fe³⁺ ion, and the thickness of PA film, it was found that Fe³⁺ ion could not penetrate into the PA film and thus the electron cross-exchange reaction between Fe³⁺ ion and the reduced form of PA film occurred substantially at the PA film/solution interface. In this case, the limiting current was controlled by the mass transport of Fes+ ion from the bulk of solution to the PA film/solution interface; it was not controlled both by the electron transfer reaction within the PA film and by the electron cross-exchange reaction between Fe³⁺ ion and the reduced form of PA film. As a result, almost same limiting current values were observed at uncoated and PA-coated BPG electrodes. The oxidation of [Fe(CN)₆]^4- and [W(CN)₈]^4-ions and the reduction of [Fe(CN)₆]^3- ion at PA-coated BPG electrodes occurred at the PA film/solution interface.
In addition, on the basis of the results obtained, the usefulness of the PA-coated electrodes as electron-transfer catalyst and mediator was discussed.

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A presynaptic membrane model device was fabricated by the electrooxidative polymerization of pyrrole onto a platinum electrode in aqueous solutions in a form of polypyrrole thin film. The device was proved to incorporate anionic neurotransmitters such as glutamic acid and aspartic acid at an electrochemically oxidized state of polypyrrole. Electric stimulation caused the device to release the incorporated neurotransmitter due to the electrochemical neutralization of polypyrrole. The rate of electrochemical incorporation and release of neurotransmitters was found to reflect the structure of the film, which was controlled by the size of anions presented in polymerization.

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Photoelectrochemical cell consisting of polythiophene film/Pb(ClO₄)₂/acetonitrile/Pb is studied. This cell exhibits an open circuit voltage of ca.0.8 V and a short circuit current of 0.2 mA/cm₂ with a conversion efficiency of ca. O.03% under illumination of approximately 1 sun. This photoelectrochemical cell also demonstrates the attractive feature that the polythiophene film is doped by the illumination (photocharging). This fact was confirmed by measuring the potential of polythiophene film (ca.0.97 V) against lead electrode and the absorption spectrum which shows the characteristic of doped one.
The polythiophene film which is being chemically doped in 98% sulfuric acid can be simultaneously undoped by the electrochemical means in the cell with a lead counter electrode. The fact that the cell can be discharged spontaneously for longer period indicates that the polythiophene film acts as an electrocatalyst in a fuel type cell. The cell shows the open circuit voltage of ca. O.8 V and short circuit current of about 1.3 mA/cm². It is found that the cell capacity is determined by the surface area of lead plate and that no degradation of polythiophene film occurs.

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The reductions of CO and CO₂ to organic substances have been widely carried out with various heterogeneous catalysts under very severe conditions. The purpose of this paper is to carry out such reductions at ordinary temperature using mediated electron-transfer reactions via surface-confined metal complex. Everitt's salt was used as the surface-confined metal complex. This compound is the reduced form of Prussian Blue that has been generally employed as a blue pigment. CO and CO₂ were convertible to methanol by Everitt's salt in the presence of a metal complex and a primary alcohol. These redox reactions are being composed of the reduction of CO and CO₂ to methanol and the oxidation of Everitt's salt to Prussian Blue. In this process the surface-confined metal complex is restored by an external electric energy, and operates as a mediator. At the three phase boundary(gas/solution/electrode), CO and CO₂ can be more effectively reduced than at the two phase(solution/electrode). This result is based on the fact that the diffusion of reaction gas to a reaction zone is more favorable along the electrode surface than through the bulk solution.

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Electrical resistances at high pressure, ionization potentials, absorption spectra, and lattice constants of triphenodithiazine(C₁₈H₁₀N₂S₂; TPDT) and its analogues have been studied at room. temperature. An ionization potential of TPDT film was 5.12 eV. The value is some what larger than that of TTF. The electrical resistance of TPDT rapidly decreased with increasing pressure. The least resistivity at 22 GPa was about 5×10²Ω·cm.
Various thin films of TPDT were prepared by evaporation onto glass or quartz substrates kept at room temperature or high temperatures. Absorption spectra of these thin films have been investigated as a function of crystallinity. A color of TPDT film became blue when exposed to gases of Br₂, NO₂, HCl at room temperatare. The new charge-transfer complexes were formed on the surface of TPDT film.
The physicochemical properties of the evaporated films of TPDT have been discussed.

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Relations are investigated between electrical and structural properties in organic superconductors bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF) salts. It is known that the superconductivity transition temperature T_c of β-(BEDT-TTF)₂I₃ salts is raised from 1.5 to 8 K when the sample experiences high pressures. Furthermore, at ambient pressure, an incommensurate superstructure is formed with the wave vector q= (0.08, 0.27, 0.205) below 200 K in this salt. With the hypothesis that the increase of T_c is brought about by a suppression of the growth of the superstructure, and that the superstructure is hardly formed in samples which experienced high pressures, the temperature dependence of satellite intensities is measured by X-ray diffraction in those samples. A negative result is obtained for this hypothesis. Namely the behavior of the superstructure is found to be insensitive to pressurization. However, this conclusion does not exclude the possible change of the superstructure in a small volume of crystals, which can hardly be detected by X-ray diffraction.
A salt of (BEDT-TTF)₂IBr₂ shows semiconducting properti es and its activation energy increases with decreasing temperature. It is found that a molecular dimerization occurs with temperature decreasing from room temperature. This dimerization is considered to cause the increase of the activation energy. In this salt, another structural change seems to take place near 130 K.

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Polarized extended X-ray absorption fine structure (EXAFS) and X-ray absorption near edge structure (XANES) of stretch-oriented polyacetylene doped with bromine have been measured for (CHBr_y)_x(0.004<y<0.8) on the Br K-edge using synchrotron radiation. A large anisotropy was observed between the spectra with the polarization vector E parallel and perpendicular to the fibril axis for (CHBr_y)_x in the lightly doped region (O.01<y<0.1), which is interpreted as an evidence for the existence of polybromine ion highly oriented along the c-axis. The Fourier transform analysis showed that bromines exist in the form of both polyions and substituted and/or added bromines in this region whereas most of the bromines are added to the polymer backbone in the heavily doped region (y>0.1). The absence of bromine-bromine bonds in the very lightly doped region (y<0.01) suggests that bromines might exist as ions. Even in this region, a part of the doped bromines are covalently bonded with polyacetylene. A simple structural model assuming the existence of polybromine ions and covalently bonded bromines is proposed on the basis of the dopant-concentration dependence of polarized EXAFS and XANES. This model is consistent with the bromine-concentration dependence on the electrical conductivity.

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A novel photochemical synthetic route to tetrathiafulvalene, starting from 1, 3-dithiole-2thione is described. Irradiation of 4, 5-diphenyl-1, 3-dithiole-2-thione in the presence of triethyl phosphite or triethylamine in acetonitrile gave tetraphenyltetrathiafulvalene in 91%or 53% yield, respectively. The photoinduced electron transfer from the phosphite to the 1, 3-dithiole-2-thione apparently accelerates the phosphite-promoted coupling of the 1, 3dithiole-2-thione.

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