Organic superconductor with an incommensurate anion structure:: (MDT-TSF)(AuI2)0.44 -: art. no. 140508

The degree of charge transfer and the upper critical field of the organic superconductor (MDT-TSF)(AuI2)(x) have been investigated (MDT-TSF: methylenedithio-tetraselenafulvalene). The x-ray oscillation photograph indicates that the anion lattice is incommensurate with the donor lattice, and the chemical composition is (MDT-TSF)(AuI2)(0.44). The charge-transfer degree of this salt is 0.44. The electrical resistivity and the Seebeck coefficient indicate that this salt is a good Fermi liquid above the superconducting transition temperature. The upper critical fields show anisotropic three-dimensional character in spite of the complicated incommensurate structure, and are within the Clogston-Chandrasekhar paramagnetic limit in all directions.