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Single crystals of the title compound are prepared by solid state reaction of a stoichiometric mixture of Li2MoO4, GeO2, MoO3, and Mo (arc-welded Mo crucible under reduced Ar pressure, 1923 K, 72 h).

The title compound is synthesized by solid state reaction of a stoichiometric mixture of Li2MoO4, In2O3, MoO3, and Mo (850 °C, 2 d).

Single crystals of the quaternary title oxide are obtained by arc welding of a stoichiometric mixture of Li2MoO4, SnO2, MoO3, and Mo (Mo crucible 1650 °C, 72 h).

The title compound, strontium pentamolybdate, is isostructural with LaMo 5 O 8 and therefore contains bioctahedral Mo 10 O 18 cluster units strongly linked by Mo(1)-Mo(1) intercluster bonds of 2.7651 (9) A to form infinite molybdenum oxide chains. These are interconnected through Mo-O-Mo bonds to create four-sided channels, in which the Sr 2+ cations are located. The Mo-Mo distances within the Mo 10 cluster lie between 2.6034 (6) and 2.8324 (9) A (average 2.740 A). The Mo-O distances range between 1.902 (4) and 2.148 (4) A (average 2.062 A). The Sr 2+ cation is surrounded by ten O atoms at distances ranging from 2.529 (4) to 2.935 (4) A, with an eleventh O atom at 3.219 (4) A

The kinetics of carbothermic reduction of molybdenum oxide with homogeneously mixed carbon black was studied under non-isothermal heating conditions using a thermobalance. The evolved gases (CO and CO 2 ) were analysed by a gas chromatograph. A mechanism is proposed to explain the stepwise conversion of oxide to carbide. A model representing stepwise conversion of the above reduction has been developed and the probable rate controlling steps, for different reactions, have been identified.

The hydrothermal reaction of MoO3, CuSO4·5H2O, 1,2,4-triazole and H2O produces a 50% yield of [{Cu2-(triazolate)2(H2O)2}Mo4O13], a material constructed from {Mo4O13}n2n– chains entrained within the three dimensional framework provided by the {Cu2(triazolate)2(H2O)2}n2n+ polymeric complex.

The hydrothermal reaction of MoO3 with BaH3IO6 at 180 °C for 3 days results in the formation of Ba[(MoO2)6(IO4)2O4]·H2O (1). Under similar conditions, the reaction of Ba(OH)2·8H2O with MoO3 and Ba(IO4)2·6H2O yields Ba3[(MoO2)2(IO6)2]·2H2O (2). The structure of 1, determined by single-crystal X-ray diffraction, consists of corner- and edge-sharing distorted MoO6 octahedra that create two-dimensional slabs. Contained within this molybdenum oxide framework are approximately C2v tetraoxoiodate(V) anions, IO43-, that are involved in bonding with five Mo(VI) centers. The two equatorial oxygen atoms of the IO43- anion chelate a single Mo(VI) center, whereas the axial atoms are μ3-oxo groups and complete the octahedra of four MoO6 units. The coordination of the tetraoxoiodate(V) anion to these five highly electropositive centers is probably responsible for stabilizing the substantial anionic charge of this anion. The Ba2+ cations separate the layers from one another and form long ionic contacts with neighboring o...

A novel three-dimensional molybdenum oxide Mo3O9·H2O (1) constructed from Mo3O9 units has been successfully synthesized under hydrothermal conditions and structurally characterized by IR spectrum, ...

Linked to the Pentagon: The addition of molybdate to [HBW(11)O(39)](8-) ions leads to the formation of mixed pentagonal units {W(Mo(5))} and {W(WMo(4))} trapped as linkers in the resulting modular assemblies, thus establishing the first link between the conventional Keggin ion derivatives and the giant molybdenum oxide and keplerate ions.

Functionalization via covalent grafting of organic functions allows to tune the redox and acid-base properties, and the solubility of polyoxometalates, to enhance their stability and biological activity and to reduce their toxicity, to facilitate their implementation in extended structures and functional devices. We discuss herein the electronic and binding connections, and the various synthesis methodologies. We emphasize on organonitrogen, organosilyl and organophosphonyl derivatives with special attention to synthesis, characterization and potential applications in catalysis and materials science. We also consider the giant molybdenum oxide-based clusters especially the porous capsule-type clusters (Keplerates) which have high relevance to this context.

Multicomponent BaMo2O7 single-crystalline nanowire bundles were synthesized by a hydrothermal crystallization process under mild conditions using cheap and simple bulky oxide and fluoride as precur...

Physical and catalytic properties of hydrogen molybdenum bronze, H1.55MoO3 varied markedly with H2 reduction. The surface area was enlarged from 10 m2/g to 250 m2/g by H2 reduction at 673–723 K. H1.55MoO3 became an active and selective catalyst for pentane isomerization after reduction. H2-reduced H1.55MoO3 exhibited a comparable isomerization activity to H2-reduced Pt/MoO3.

The complex of (TMA)2[Ni(H2O)6][β-Mo8O26] (I) has been synthesized via hydrothermal reaction under 130 °C. The crystal structure was determined by single crystal X-ray diffraction at room temperature. Crystal data: M=1498.62, Monoclinic, space group C2/c (No.15), a=15.9812(13) A, b=13.5690(11) A, c=16.7782(13) A, α=90°, β=96.760(2)°, γ=90°, and Z=4. It is composed of an inorganic cluster [β-Mo8O26]4−, six-hydrated bivalent nickel cation, and two organic amines TMA+.

The understanding of the fundamental principles behind the growth of materials from discrete molecules to new solid-state materials is presently a great challenge. Herein novel nanoscale polyoxometalate clusters with circular and spherical topologies are described and examples that have application in the study of molecular growth processes are highlighted. This is because it is now possible to control the formation of solid-state structures from certain types of polyoxometalate fragments that can be described as synthon-based building blocks. This ability, combined with the enormous number of ways that these building blocks can be linked together, is opening completely new and fascinating avenues for the synthesis of solid-state structures with predesigned properties.

It was found that hydrogen molybdenum bronze, H0.3MoO3, turns into a hydrogen insertion compound of hydrated molybdenum oxide in a 1M HCl aqueous solution at 353 K. It was predictable that the compound has a composition of H0.15MoO3·0.88H2O and is identical with Mo8O15(OH)16 or a similar compound.

The Raman spectrum of a calcined (773 K, 5 h, air) Mo/SiO2 catalysts of high Mo loading (20 wt.%) is identical with that of MoO3, whereas EXAFS results indicate that MoO3 is not the dominant species in the 20 wt.% Mo catalyst.

The adsorption of ammonia and pyridine on Mo–Ti oxide (2.0 and 5.0 wt%) has been studied by i.r. spectroscopy. Mo–Ti oxide exhibits both Bronsted- and Lewis-acidic sites. The Lewis-acidic sites are converted into Bronsted sites on the introduction of water vapour. The Bronsted sites determined from pyridine adsorption are smaller in number than those from ammonia adsorption. It is found that ammonia is adsorbed in three forms: on Lewis sites, on surface OH groups as NH4+ and as NH2 species, resulting in the increase in Bronsted sites.

IR and XRD analysis indicate a solid state reaction between MoO3 and NiO in different ratios at ∼500 °C. In the presence of 70 mol% Ni2+, formation of the NiMoO4 spinel is observed.