RESEARCH ON TRINUCLEAR MOLYBDENUM CLUSTER COMPOUNDS——CRYSTAL AND MOLECULAR STRUCTURE OF （Et4N）2[Mo3（μ3-O）(μ3-Cl)（μ2-Cl）3Cl6]·EtOH

The title crystal belongs to the monoclinic system. The space group is P2/c with unit cell parameters: a=11.379（3）, b=20.766（2）, c=14.487（3）, β=91.49（2）°, V=3519（2）Z=4, D=1.819g.cm, D=1.81g.cm. The crystal structure was solved by the heavy atom method and difference Fourier synthesis and refined by the full-matrix least-squares to a final R factor of 0.040 based on 3261 unique reflections with intensities I≥3σ（I）. The structure consists of two sots of tetraethylammonium cations and trinuclear Me cluster anions. In the cluster anion the three Mo atoms form an isosceles triangle with Mo-Mo distances of 2.601（1）, 2.608（1）, 2.642（1）, respectively, showing a strong bonding interaction between the metal atoms. One μ-O atom and one μ-Cl atom are situated above and below the triangle respectively, binding the three Me atoms to form a triangular bipyramidal cluster core. Each pair of Mo atoms is bridged further by a μ-Cl atom situated on the Motriangular plane. In addition, each