Yasuo Ishizaki

Formation of two-dimensional weak localization in conducting Langmuir-Blodgett films

We report the magnetotransport properties up to 7 T in the organic highly conducting Langmuir-Blodgett(LB) films formed by a molecular association of the electroactive donor molecule bis(ethylendioxy)tetrathiafulvalene (BEDO-TTF) and stearic acid CH

Metallic Langmuir and Langmuir-Blodgett films based on TTF derivatives and fatty acid

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Conducting properties of Langmuir-Blodgett films based on BEDO-TTF

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Preparation of a new conducting Langmuir-Blodgett films based on oxygen substituted TTF derivative

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ESR properties of Langmuir–Blodgett films based on BO and behenic acid

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Langmuir-Blodgett Films of Bedo-TTF / Behenic Acid : Effect of the Molecular Fraction of Bedo-TTF and of the Substitution of Behenic Acid for other Amphiphilic Molecules

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Observation of two-dimensional weak localization as a sign of coherent carrier transport in the conducting Langmuir-Blodgett films of BEDO-TTF and stearic acid

COOH. We show the logarithmic decrease of dc conductivity and the negative transverse magnetoresistance at low temperature. They are interpreted in the weak localization of two-dimensional (2D) electronic system based on the homogeneous conducting layer with the molecular size thickness of BEDO-TTF. The electronic length with phase memory is given at the mesoscopic scale, which provides for the first time evidence of the 2D coherent charge transport in the conducting LB films.

Effect of UV irradiation on conducting LB films of BEDO-TTF and stearic acid

Abstract Recent progress in the metallic conducting Langmuir–Blodgett (LB) films built from TTF derivative and fatty acids is reported. A simple LB method of transferring the mixed Langmuir (L) film of BEDO-TTF (BO) and stearic acid (SA) onto substrates provided metallic conducting LB films. A homogeneous L film formation on the water surface observed by Brewster angle microscope (BAM) is an essential factor for the well-ordered LB films. In the L film, the carboxylate group of fatty acid forms anion layer bringing about a spontaneous formation of mixed valence state (MVS) of BO layer. Similar spontaneous formation was also found in the molecular combination of nonoxygen-substituted donor of EDT-TTF and octadecanesulfonic acid (OS). This type of reaction would be useful for obtaining conducting LB films. For the LB films of BEDO-TTF and stearic acid, we found a negative transverse magnetoresistance at low temperature that was interpreted in the weak localization of a two-dimensional (2D) electronic system based on the well-defined conducting layer.

Absorbance of UV-irradiated BO-SA LB films

We report the conducting properties of Langmuir-Blodgett (LB) films based on the donor molecule BEDO-TTF associated with amphiphilic molecules. FTIR and dc conductivity measurements were performed and discussed as a function of the nature of the amphiphilic molecule mixed with BEDO-TTF.

Formation of spontaneous charge-transfer salt in the molecular system of EDT-TTF and long alkyl-chained sulfonic acid

Abstract A new conducting Langmuir-Blodgett (LB) film is fabricated from bis-ethylenedioxy-diselenadithiafulvalene (BEDO-STF) and behenic acid. Physical properties of the present LB films are investigated by the measurements of surface pressure — area isotherms, X-ray diffraction, FT-IR, and room temperature conductivity. These results are compared with those of BEDO-TTF and behenic acid LB films. The layered structure for both LB films are very similar to each other. The similarity is suspected to be brought about by the strong interaction between these oxygen substituted TTF donors and RCOO − part of behenic acid. On the other hand, significant differences in infrared property and room temperature conductivity are observed. The in-plane structure in a microscopic range may cause the differences.