Synthesis, crystal structure and photoconductivity of new molecular complex of C60 with tetrabenzo(1,2-bis[4H-thiopyran-4-ylidene]ethene): Bz4BTPE C60 Original Research Article

A new molecular complex of C60 with tetrabenzo(1,2-bis[4H-thiopyran-4-ylidene]ethene), Bz4BTPE C60 (1) has been obtained. The complex has a layered structure in which closely packed hexagonal layers of C60 alternate with the layers composed of Bz4BTPE molecules. The complex has a neutral ground state according to UV–vis–NIR spectrum. It has been found that single crystals of 1 show low ‘dark’ conductivity of σ∼10−10 (Ω cm)−1. A 102 increase in photocurrent has been observed upon illuminating the crystal with white light. Photoconductivity of 1 is sensitive to magnetic field with B0<1 T and increases up to 5% in magnetic field. The photoconductivity spectra of the complex indicate that free charge carriers are generated in the UV–visible range mainly by the Bz4BTPE excitation (the peaks at 622, 562, 472 and 348 nm) with a possible contribution of charge transfer excitations between neighboring C60 molecules (the peak at 472 nm).