Two series of O-alkyl dithiocarbonate (xanthate) derivatives of dimethyl- and diphenyltellurium(IV), Me(2)Te[S-2-COR](2) and Ph(2)Te[S(2)COR](2), where R = Me, Et, i-Pr, n-Pr, and n-Bu, have been prepared in 60-71% yields by the reaction of the potassium salt of!the appropriate dithiocarbonic (xanthic) acid with dichlorodimethyltellurium-(IV). The products were characterized principally by infrared, Raman, and H-1, C-13, and Te-125 NMR spectroscopy. The crystal structures of Me(2)Te[S(2)COE](2) and Ph(2)Te[S(2)COEt](2) were determined. Me(2)Te[S(2)COEt](2) (2) crystallizes in space group (P $($) over bar$$ 1, No. 2) with the cell parameters a = 10.588(2) Angstrom, b = 11.974(2) Angstrom, c = 6.458(3) Angstrom, alpha = 104.06(3)degrees, beta = 90.67(2)degrees, gamma = 7125(1)degrees, V = 770.2(8)Angstrom(3), and Z = 2; R = 0.0310, R(w) 0.0286. Ph(2)Te[S-2-COEt](2) (7) also crystallizes in space group (P $($) over bar$$ 1, No. 2) with the cell parameters a 11.320(3) Angstrom, b = 13.062(4) Angstrom, c = 8.225(4)Angstrom, alpha = 107.88(3)degrees, beta = 110.72(3)degrees, gamma = 79.91(3)degrees, V = 1078.3(8) Angstrom(3), and Z = 2; R = 0.0366, R(w) = 0.0329. The immediate environment about tellurium in both molecules is essentially that of a sawhorse structure in which the lone pair is !apparently stereochemically active and occupies an equatorial position in a distorted trigonal bipyramid. The two methyl or phenyl groups occupy the other equatorial positions with Te-C bond lengths of 2.104(6) and 2.125(6) Angstrom and a C-Te-C angle of 96.2(2)degrees in 2. The corresponding values for 7 are 2.127(5) and 2.139(5) Angstrom and 99.3(2)degrees. The axial positions are occupied by a sulfur atom from each of the dithiocarbonate groups to give anisobidentate linkages resulting in Te-S bonding distances of 2.590(2) and 2.677-(2) Angstrom, an S-Ge-S angle of 16638(5)degrees, and S-Te-C angles ranging from 82.3(2) to 90.9(2)degrees in 2.