Tungsten oxyfluoride

Zmbov et al. (1 ) Investigated the stabilities of some molybdenum and tungsten oxyfluorides by means of mass spectrometry. These studies led to enthalpies of formation for MoO F Cg), WO F (g), and WOF (g) which were used by the authors to develop a correlation among the enthalpies of formation of the oxides, oxyfluorides, and fluorides of Mo and W. a H (298.15 K) varies almost linearly with the number of oxygen atoms (1 ) for the series WF, WOF and VO o Assuming a similar variation for MoFg, MoOF and... 

A rich variety of complex oxyfluoride compounds containing tungsten, molybdenum, and titanium and displaying spontaneous polarization was discovered and described in [396 - 399]. 

The second group is the group of oxyfluorides that are derived from ferroelectric oxides by means of fluorine-oxygen substitution. The basic oxides are usually perovskite, tetragonal tungsten bronze, pyrochlore, lithium tantalate etc. [400]. 

The reaction of W03 and tungsten metal in the presence of dilute solutions of HF under hydrothermal conditions has been shown to produce the series of tetragonal oxyfluoride bronzes (0.03 x 0.09).491 The phases CsvM2, .WvX6... 

Whereas the Mobil process starts with syn gas based methyl alcohol, Olah s studies were an extension of the previously discussed electrophilic functionalization of methane and does not involve any zeolite-type catalysts. It was found that bifunctional acidic-basic catalysts such as tungsten oxide on alumina or related supported transition metal oxides or oxyfluorides such as alumina or related supported transition metal oxides or oxyfluorides such as tantalum or zirconium oxyfluoride are capable of condensing methyl chloride, methyl alcohol (dimethyl ether), methyl mercaptan (dimethyl sulfide), primarily to ethylene (and propylene) (equation 65) . 

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