New Si-Ge and Si-Ge-Sn compounds bearing the bulky groups-E(SiMe3)3 (E = Si,Ge) were obtained by treatment of MCl4(M=Ge,Sn) with either (THF)3LiSi(SiMe3)3 or (THF)2.5LiGe(SiMe3)3. The cyclic tetragermane [(Me3-Si)3SiGeCl]4-C6H6 crystallizes in the monoclinic space group C2/c with a = 21.835(7) angstrom, b = 26.342(9) angstrom, c = 14.464(4) angstrom, beta = 103.45-degrees, V = 8092 angstrom3, and Z = 4. The Ge4 ring was nonplanar with an average torsion angle of 17.2-degrees. The tetragermane [(Me3Si)3GeGeCl2]2 Was characterized by elemental analyses and NMR spectra, which were consistent with a linear tetragermane backbone for the molecule. Dichlorobis(tris(trimethylsilyl)germyl)tin(IV), ((Me3Si)3Ge)2SnCl2, crystallizes in the monoclinic space group C2/c with a = 16.106(4) angstrom, b = 10.034(2) angstrom, c = 47.375(11) angstrom, beta = 90.02-degrees, V = 7656 angstrom3, and Z = 8. The coordination geometry around tin is extremely distorted with Ge-Sn-Ge = 142.1-degrees and Cl-Sn-Cl = 98.8-degrees. The three compounds were stable in air except ((Me3Si)3Ge)2SnCl2 was mildly hygroscopic. Reactions of the compounds with Li, LiAlH4, and (THF)2.5LiGe(SiMe3)3 were carried out, but no new products were identified. Treatment of LaCl3 with 3 equiv of (THF)3LiSi(SiMe3)3 afforded (THF)La(Si(SiMe3)3)2Cl as a very hygroscopic white solid. All attempts to substitute more than two -Si(SiMe3)3 groups on a central atom were unsuccessful.