Tetrathiafulvalen (TTF) and tetraselenafulvalen (TSF) salts with diorganochloro-stannate anions, [TTF][SnEt 2Cl 3] ( 1), [TTF] 2[SnPh 2Cl 4] ( 2), [TTF] 3[SnEt 2Cl 4] ( 3), [TTF] 3.3[SnPh 2Cl 4] ( 4), [TSF] 2[SnPh 2Cl 4] ( 5) and [TSF] 3.3[SnPh 2Cl 4] ( 6), were prepared by the reactions of [TTF or TSF] 3[BF 4] 2 with SnR 2Cl 2 (R = Et or Ph) in the presence of [Ph 3PCH 2Ph]Cl and by electrocrystallization of TTF or TSF in acetonitrile containing SnR 2Cl 2 and [Ph 3PCH 2Ph]Cl. All the salts behave as semiconductors with electrical resistivities of the order of 10–10 8 Ω cm as compacted samples at 25°C. Electronic reflectance spectra of the simple salts 1, 2 and 5, show a band due to the dimeric(TTF +) 2 or (TSF +) 2 unit in the 12,200–12,800-cm −1 region. The complex salt 3 exhibits a TTF +/TTF° charge-transfer (CT) band at 8700 cm −1, and the remaining complex salts, 4 and 6, both display CT bands between the radical cations and between the radical cation and the neutral donor molecule. The crystal structure of 3 was determined by a single-crystal X-ray diffraction. The tetragonal crystal, space group I4 cm, has cell dimensions a = 11.710(3) Å, c = 25.242(7) Å, and Z = 4. The structure was solved by the heavy-atom method and refined to a final R value of 0.082 for 479 independent reflections with > F ° > 3σ( F). TTF molecules exist as trimers, in which a slight lateral shift from the eclipsed TTF overlap occurs, although TTF molecules are arranged with equal spacing between them. The trimer units are located perpendicularly to each other, forming a two-dimensional layer. The [SnEt 2Cl 4] 2− anion is disordered with respect to the two SnEt and two SnCl bonds.