O-Alkyl dithiocarbonate (xanthate) derivatives of halodimethyltellurium(IV), Me(2)TeX[S(2)COR], where R = Me, Et, and i-Pr and X = Cl, Br, and I, have been prepared in 75-88% yields by the reaction of the potassium salt of the appropriate dithiocarbonic acid with dimethyltellurium dihalide in equimolar ratio. The compounds were characterized by infrared, Raman, and H-1, C-13, and Te-125 NMR spectroscopy. The crystal structures of Me(2)-TeCl[S(2)COEt] (2) and Me(2)TeI[S2CO(i-Pr)] (9) were determined. Me(2)TeCl[S(2)COEt] (2), which crystallizes in the monoclinic space group P2(1)/a (No. 14), has the cell parameters a = 9.583(2) Angstrom, b = 10.264(3) Angstrom, c = 22.502(2) Angstrom, beta = 97.86(1)degrees, V = 2192.4(8) Angstrom(3), and Z = 8, and Me(2)TeI[S2CO(i-Pr)] (9), which crystallizes in the triclinic space group P1 (No. 2), has the cell parameters a = 11.332(5) Angstrom, b = 11.83(2) Angstrom, c = 10.19(2) Angstrom, alpha = 94.8(2)degrees, beta = 105.53(7)degrees, gamma = 85.10(7)degrees, V = 1309(3) Angstrom(3), and Z = 2. The immediate environment about tellurium in both molecules can be described as that of a sawhorse structure in which the lone pair is apparently stereochemically active and occupying an equatorial position in a distorted trigonal bipyramid. The two methyl groups occupy the other equatorial positions with a sulfur atom of the dithiocarbonate group and a halogen atom occupying the axial positions. However, intermolecular Te-I interactions between the two molecules of the asymmetric unit of 9 suggest that it is better described as dimeric, whereas the intermolecular Te-Cl associations in 2 lead to polymeric strands rather than dimers. Supramolecular associations are discussed in terms of Pauling bond orders.