SYNTHESIS, CRYSTAL-STRUCTURE, AND ELECTRONIC-STRUCTURE OF IN2LI2NB6CL18

The synthesis and the single-crystal X-ray structure analysis of a new niobium Cluster compound are reported in this paper. In2Li2Nb6Cl18 wa s obtained by solid state reactions of stoichiometric amounts of NbCl5 , niobium metal, LiCl, and InCl3 at 820-degrees-C. The structure was r efined in the space group P1BAR (Z = 1) with a = 922.0 (2) pm, b = 927 .2 (3) pm, c = 926.7 (2) pm, alpha = 119.28 (2)-degrees, beta = 96.51 (2)-degrees, gamma = 105. 14 (3)-degrees, R = 0.035 and R(W) = 0.035, for all 3675 symmetry-independent reflections. The structure contains isolated (Nb6Cl12i)Cl6a clusters, separated by lithium and indium cati ons in a tetrahedral and a cubeoctahedral chloride coordination enviro nment, respectively. Indium is present as In+ with the 5s state being filled with two electrons, energetically lying at the bottom of the Nb 4d block. (C) 1994 Academic Press, Inc.