No abstract

C5H5)2ErC=CC(CH3)3]2 has been synthesized by the halide-free reaction of [(C5H5)2ErCH3]2 with HC=CC(CH3)3 and characterized by spectroscopic, analytical, and crystallographic methods. The title compound crystallizes from THF in the triclinic space group FT with unit cell dimensions a -3.602 (3) K,b = 8.767 (3) Á, c = 10.216 (5) Á, a = 77.86 (3)°, ß = 84.50 (3)°, 7 = 76.61 (3)°, and Z = 1 (dimer) for Z)c = 1.71 g cm-3. Full-matrix least-squares refinement led to a final R value of 0.065 based on 1321 observed reflections. The two (C5H5)2Er units in the dimer are connected by asymmetrical alkynide bridges with independent Er-C bond lengths of 2.42 (2) and 2.47 (2) Á and Er-C=C angles of 149 (2) and 115 (2)°. Isopiestic studies indicate that this complex is also dimeric in THF solution. [(CH3C5H4)2Yb-C=CC(CH3)3]2 was prepared analogously. Aluminated Metal Alkylidyne Complexes. 2.1 Crystal and Molecular Structure of W(CAl2Me4Cl)(CH3)(PMe3)2(772-C2H4)

No abstract

C,H,),Lu(But), synthesized from [(C,H,),Lu-Cl], and ButLi in pentane-tetrahydrofuran at -78 OC, crystallizes from toluene as a monomeric tetrahydrofuran solvate which contains a 2.37 k Lu-C (T bond and a short (2.31 A) Lu-0 distance; the analogous erbium complex is prepared similarly but, in the ytterbium case, the reaction generates (C,H,),Yb.

Conductive (150 μΩ cm), adherent films of zirconium and hafnium borides have been deposited on various substrates by the low-temperature (100–270 °C) thermal decomposition of Zr[BH4]4 and Hf[BH4]4. Auger electron spectroscopy of these films shows that their composition is ZrB2 and HfB2. The film surfaces are oxidized and slightly carbon contaminated. However, the bulk contains less than 1 at. % C or O. This synthesis is by far the lowest temperature preparation of these materials (plasma-enhanced chemical vapor deposition of TiB2 requires 480–600 °C) and holds great promise for the use of these materials in electronics applications.