Halide, Oxyhalide, and Related Complexes

The chemical transport of molybdenum and tungsten as oxides or sulphides in the presence of iodine has been shown to proceed by the formation of the corresponding M02I2 complex.510 

Molybdenumfvi) and Tungsten(vi).—Halide, Oxyhalide, and Related Complexes. The MF6-XeF2 (M = Mo or AV) binary systems have been studied by 

Detailed i.r, studies of WOF4(s) have been reported which strongly support the proposal (Vol. 2, p. 158) that this compound contains fluorine atoms in the bridging positions of the tetrameric units. Rb3[Mo02Fj] reacts with HF and Ce02 at 750 over 33 h to form Rbi2CeMo308Fi8, the X-ray diffraction characteristics of which have been determined.  

The molecular structures of M0OCI4 and WOCI4 have been determined by gas-phase electron-diffraction techniques. Both molecules have the expected square-pyramidal structure (86) with the metal atom some 50 pm above 

Preparative routes to M02Br2 (M = Mo or W) have been described in which the metal is oxidized with an excess of Br2, in the presence of SO2, in a sealed tube at 400°C. AggW04l4 has been identified in the Agl-AgjWO system at ambient temperatures.  

The preparation. X-ray diffraction characteristics, and other physical properties of the salts K3[MOS3X] (M = Mo or W X = Cl or Br) have been described. The new compounds Mo3Br4Y7 (Y = S or Se) have been synthesized by treating MoBr2 or MoBrj with the chalcogen at temperatures between 340 and 430 °C i.r. spectral data were obtained. WSCI4 reacts with 1,2-di- 

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