Synthesis, crystal structure and photoconductivity of the first [60]fullerene complex with metal diethyldithiocarbamate:: {CuII(dedtc)2}2•C60

The first molecular complex of fullerene C-60 with metal dithiocarbamate, namely, {Cu-II(dedtc)(2)}(2)center dot C-60 (dedtc: diethyldithiocarbamate) (1) was obtained as single crystals. Butterfly-shaped CuII( dedtc) 2 molecules efficiently co-crystallized with spherical fullerene molecules to form a layered structure, in which closely packed hexagonal C-60 layers alternate with the layers composed of Cu-II(dedtc)(2) dimers. The formation of the complex with C-60 changes geometry and the EPR spectrum of starting Cu-II(dedtc)(2). Magnetic susceptibility of 1 follows the Curie-Weiss law in the 300-1.9 K range with the negative Weiss constant of -2.5 K showing a weak antiferromagnetic interaction between Cu-II centers in the dimers. The crystals of 1 have low dark conductivity of 10(-1)1 S cm(-1), which is consistent with a neutral ground state of the complex. Illumination of the crystals by white light increases the photocurrent by 20-50 times. The photoconductivity spectrum of 1 has a maximum at 470 nm showing that both intermolecular charge transfer between neighboring C-60 molecules and photoexcitation of Cu-II(dedtc)(2) can contribute to photogeneration of free charge carriers. The effect of a weak magnetic field with B-o<0.5 T on the photoconductivity of 1 has been found.