Molecular complex of [60]fullerene with 2-(4-thione-1,3-dithiolan-5-yliden)-4,5-dimethyl-1,3-diselenol [C-60 center dot 2(DTDS)]: Synthesis, crystal structure and properties

New molecular complexes of [60]fullerene with 2-(4-thione-1,3-dithiolan-5-y liden)-4,5dimethyl-1,3-diselenol [C-60.2(DTDS)] have been synthesized, crys tal structure, IR spectral and electrochemical properties have been studied . Partial charge transfer has been found. An unusual shortening of the endo cyclic S-C(sp(2)) bond in the DTDS molecule has been found to be stipulated by conformational vibrations of the >CH2 group. A comparative analysis of the X-ray data for the [C-60. (DTDS)] crystals and the quantum chemical cal culations (SCF MO, 6-31G* basis) for the DTDS molecules and its radical ion s showed charge transfer not to be the cause for the shortening of the exoc yclic C=S bonds.