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The electrical and optical properties were studied concerning α-(BETS)2I3 and α-(BEDT-STF)2I3, which are isostructural to α-(BEDT-TTF)2I3. It has been shown that α-(BETS)2I3 and α-(BEDT-STF)2I3 undergo metal-insulator transitions at around 50 and 80 K, respectively, and that their electrical resistivities exhibit temperature dependences resembling that of α-(BEDT-TTF)2I3 under high pressure. The optical reflectance spectra of these salts show a two-dimensional nature of their electronic structures, and analyses of the spectral data show that the transverse inter-molecular interaction increases in the order α–(BEDT–TTF)2I3 < α–(BEDT–STF)2I3 < α–(BETS)2I3.

The donor-acceptor type molecular conductor, α-(EDT-TTF)[Ni(dmit)2], was found to be a superconductor under ambient pressure below 1.3 K. This is the first ambient-pressure superconductor in a series of M(dmit)2 salts [M = Ni, Pd, Pt]. The sample dependence and magnetic-field dependence on the superconducting transition are described.

We first succeeded in preparing ferromagnetic materials of SmCo(5) nanoparticles in sizes of single nanometers by a chemical route using a polyol process. In order to produce ferromagnetic SmCo(5) nanoparticles with a CaCu(5)-type structure, the chemical preparation was conducted under a molar ratio of 1:1.3 of Sm:Co as compositions of metallic precursors when tetraethylene glycol (TEG), and oleic acid and oleylamine were used as a reductant and protectant, respectively. However, XRD profiles of the products showed the presence of oxides and other by-products besides the CaCu(5)-type structured nanoparticles. The best metallic precursors and protective reagent to prevent oxidization under reaction were SmCl(3) and Co(acac)(3), and 1-adamantanecarboxylic acid (ACA) and poly(N-vinyl-2-pyrrolidone) (PVP), respectively when TEG was used as the reducing reagent. We found that oxides and other by-products were not detected and pure SmCo(5) nanoparticles with the CaCu(5)-type structure were prepared under the chemical condition. The SmCo(5) nanoparticles coated by ACA and PVP were 6.2 nm in diameter and showed a coercivity of 1500 Oe at 300 K.