Molybdenum oxide, single crystals

Molybdenum(IV) Oxide and Tungsten(IV) Oxide Single Crystals 149... 

MOLYBDENUM(IV) OXIDE AND TUNGSTEN(IV) OXIDE SINGLE CRYSTALS... 

We begin with the structure of a noble metal catalyst. The emphasis is on the preparation of rhodium on aluminum oxide and the nature of the metal-support interaction. Next we focus on a promoted surface in a review of potassium on noble metals. This section illustrates how single crystal techniques have been applied to investigate to what extent promoters perturb the surface of a catalyst. The third study deals with the sulfidic cobalt-molybdenum catalysts used in hydrotreating reactions. Here we are concerned with the composition and structure of the catalytically active... 

The Mo(IV) aqua ion was first reported by Souchay et al. as a monomeric species in 1966 (93), and the Mo3044+ core structure has been confirmed by single-crystal X-ray structure analyses, as described in this review, 95Mo NMR (94), EXAFS structure analysis (95), and 180-labeling experiments (96), after the appearance of many contradictory reports (97). Information on the reduction products of the Mo(IV) aqua ion is also available (98), Richens and Sykes have summarized the preparation of the different aqua ions of molybdenum in oxidation states II to V (99). 

Theoretical studies on molybdenum oxide surfaces have focused exclusively on single crystal surfaces of M0O3 and M0O2 that are described by low Miller indices. This is due to their relatively simple geometry considering the... 

Two octamolybdenum compounds, containing both bridging pyrazolate and terminal pyrazole ligands, [Mo8(pz)6(0),8(Hpz)6], 177, and [Mo8(pz)6-(0)2,(Hpz)6], 178, were prepared by the reaction of molten pyrazole with molybdenum oxides and their structures were determined by single-crystal X-ray diffraction (133). The overall geometries of 177 and 178 are similar. Both complexes consist of an octametallic framework that may be described as two bas-ally connected flattered trigonal pyramids. 

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