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Abstract: We have obtained several charge-transfer complexes of CnDTP-TTF (n =5,6). The C5DTP-TTF salts are the κ-type semiconductor with high room-temperature conductivities, whereas β′′-(C6DTP-TTF)2(GaCl4)0.66 shows the metallic behavior down to 40K. In order to improve the conductivity by increasing the bandwidth, we have applied a pressure and synthesized a series of the selenium analogues, CnDTP-STF (n =5,6). In this report, crystal structures and conducting behaviors of CnDTP-TTF salts, and the attempt of increasing the bandwidths are described. [Copyright &y& Elsevier]

The transverse magnetoresistance has been measured in (TMTSF)2PF6 under pressure, with the field parallel to the c* axis. At 0.85 GPa, the spin-density-wave (SDW) transition temperature TSDW increases quadratically with the applied magnetic field, and a saturation behavior is observed in high magnetic fields. These results are consistent with the mean field theory. From these behaviors, TSDW for the perfect nesting case, Fermi velocity and imperfect nesting parameter at 0.85 GPa are estimated as TSDW0=14.5 K, vF=8.55×104 m/s and ϵ0/Δ0=0.996 using the mean field theory, respectively. The SDW phase diagram of (TMTSF)2X can be described by taking into account the reduction of the coupling constant by the pressure. [Copyright &y& Elsevier]

Abstract: A new series of RDT-EDO-TTF [R =C5, C6, C7, C8; (cis-l,2-cycloalkylene-l,2-dithio)ethylenedioxytetrathiafulvalene and R =Bz; (benzodithio)ethylenedioxytetrathiafulvalene] donors containing cycloalkylene or benzene, and ethylenedioxy groups as a source of the steric hindrance and the intermolecular hydrogen bonds has been synthesized. The charge transfer (CT) salts, β″-(RDT-EDO-TTF)2(PF6)x (R =C5, C6, C7, C8, and Bz), have the similar β″-type donor arrangement due to the intermolecular hydrogen-bonded network (CH…O) in the two-dimensional (2D) plane. The C6DT-EDO-TTF molecule containing the flexible cyclohexylene group affords the 2:1 salts, which shows the metallic behaviors down to 1.3K with a variety of resistivities at room temperature, 3.0×10−3∼5.0×10−2 ohmcm. On the other hand, the BzDT-EDO-TTF donor with the fixed functional benzo group gives the non-stoichiometry complexes, which exhibit the similar metallic behavior down to 1.3K with the largest RRR=40∼115 among the RDT-EDO-TTF salts. [Copyright &y& Elsevier]

Abstract: Thin film waveguides of polyphenylenevinylene were formed on a distributed feedback resonator. Light emission under pulsed optical pumping was measured as a function of excitation wavelengths. A distributed feedback lasing appeared constantly at 635nm. In addition, an emission peak due to stimulated resonant Raman scattering emerged and its peak position shifted according to the excitation wavelength. When the latter peak just overlapped with the former one, the emission intensity was enhanced and its peak width and background noise by amplified spontaneous emission were reduced. The coupling of Raman scattering with the feedback mode would be a useful technology for development of a plastic laser. [Copyright &y& Elsevier]