Sealed tube reactions of titanium, sulfur, and sulfur monochloride give Ti40(S2)4Cl6, 1, and Ti40(S2)4Cl6-2S8, 2, depending on conditions. Each compound was characterized by single-crystal X-ray diffraction studies. Crystallographic parameters are as follows. Compound 1: monoclinic space group Fife•, a = 9.078 (4) k,b= 11.007 (4) Á, c = 18.388 (6) Á, ß = 91.95 (3)°, V = 1836 (2) Á3, and dcilcd = 2.448 g/cm3 for Z = 4. The structure was refined to R = 0.045 and Rw = 0.055 for 1787 reflections having I > 3 ( ). Compound 2: orthorhombic space group Pbcn; a = 27.820 (11) A, b = 9.262 (4) Á, c = 13.602 (5) A, V = 3505 (4) Á3, and dcaici = 2.255 g/cm3 for Z = 4. The structure was refined to R = 0.040 and Rw = 0.048 and 937 reflections with I > 3 (7). Compound 1 consists of Ti40(S2)4Cl6 molecules having idealized Z)2¿ symmetry. A flattened tetrahedron of Ti atoms with an oxygen atom in the center has four short disulfide bridged Ti-Ti contacts of 3.123 [4] Á and two longer Cl bridged Ti-Ti distances of 3.562 [5] Á. Compound 2 contains essentially identical molecules cocrystallized with S8 molecules. Molecular orbital calculations on compound 1 by the Fenske-Hall method performed in an attempt to understand the metal-metal interactions suggest that there are no Ti-Ti bonds between any pair of metal atoms. The closer Ti-Ti distances can be attributed to strong bridging interactions by the S2 groups.Over the past several years an increasing research effort has focused on the field of early transition-metal cluster chemistry. This work has resulted in the discovery of many metal atom clusters, both discrete and extended. A large number of such compounds are known for molybdenum oxides (e.g., InMo406, NaMo204, Ca5 45Mo180 32, Zn3Mo308,* K2Mo80¡8,7 and 40 623) as well as for niobium, zirconium, and lanthanide halides (e.g.,
