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Polyoxometallates

The polyoxometallates constitute a very large class of compounds which includes most of the complexes to be discussed below. They have in the past been divided into (a) isopoly anions, M O , and (b) heteropoly anions, A M OJ , where M = Mo, W, V, Nb, Ta, Ti A = P, As, Sb, Si, Ge, B, etc. [Pg.293]

It is now accepted that A and M can represent a much wider variety of elements than these, however. The boundaries between (a) and (b) have been blurred by the new types of structure constantly being reported and the general term polyoxoanions is considered more appropriate by some. [Pg.293]


SPECTROPHOTOMETRIC DETERMINATION OF PHOSPHATE AND ARSENATE IONS BY MEANS OF IONIC ASSOCIATES OF CYANINE DYES WITH POLYOXOMETALATES... [Pg.87]

A reaction of mixed molybdenum polyoxometalates (POMs) with cyanine dye has been used for highly selective and sensitive spectrophotometric determination of phosphorus(V) and arsenic(V). Color of the solution is considerably changed by reaction of Keggin POMs with styrene cyanine dyes. Derivatives of l,3,3-threemethyl-3//-indol - astrazone violet (AV 3R), astrazone rose, astrazone yellow, astrazone red were investigated. [Pg.87]

EXTRACTION-SPECTROPHOTOMETRIC DETERMINATION OF PHOSPHATE AND ARSENATE USING IONIC ASSOCIATES OF POLYOXOMETALATES WITH BASIC DYES... [Pg.125]

Different extraction-spectrophotometric procedures were proposed for the P(V) and As(V) determination as ionic associates (lA) of polyoxometalates with basic dyes. Main disadvantage is difficulty in separation of reagent excess. Flotation, centrifugation or extraction does not allow to create sufficiently sensitive procedures due to worsening of reproducibility. [Pg.125]

It is shown that both Sb(III) and Bi(III) can speed reduction of 12-molybdophosphate (12-MPC) to the corresponding heteropoly blue (12-MPB) by ascorbic acid (AA). It is found that mixed polyoxometalates can be formed in solution which reduce considerably more rapidly than 12-MPC. Complete formation of mixed POM is observed only if significant excess of Me(III) ions is used in the reaction. POM responsible for blue color was synthesized by selective extraction. Chemical analysis of tetrabutyl-ammonium salt is in accordance with formula of (TBAl PMeflllfMo O j (Me = Sb, Bi). IR spectmm of mixed POM is identical to 12-MPC. [Pg.156]

Ionic associates (lA) of polyoxometalates (POMs) with threephenylmethane dyes remain as perspective analytical forms for the determination of some nonmetals including P(V), As(V) and Si(IV). Several reasons hinder to the improvement of analytical characteristics of these reactions. Separation of dye excess and its lA with reagent are most important Procedure for extractive separation is often timeconsuming, complex and does not allow complete separation from reagent excess. [Pg.285]

Polyoxometalate Symposium Report (Engl.), Comptes RendusAcad. Sci. He, 1, 297-403 (1998). [Pg.1009]

Tributsch H (1982) Photoelectrochemical Energy Conversion Involving Transition Metal d-States and Intercalation of Layer Compounds. 49 127-175 Truter MR (1973) Structures of Organic Complexes with Alkali Metal Ions. 16 71-111 Tytko KH, Mehmke J, Kurad D (1999) Bond Length-Bond Valence Relationships, With Particular Reference to Polyoxometalate Chemistry. 93 1-64 Tytko KH (1999) A Bond Model for Polyoxometalate Ions Composed of M06 Octahedra (MOk Polyhedra with k > 4). 93 65-124... [Pg.256]

Troupis EGA, A Hiskia, E Papaconstantinou (2005) Photochemical reductaion and recovery of mercury by polyoxometalates. Environ Sci Technol 39 4242-4248. [Pg.47]

Figure I. Oxygen uptake by supported clusters and vanadium oxide. Samples were pre-reduced and re-oxidized at the temperatures indicated on the abscissa. Silica-supported polyoxometalates PVl ( ), PV3 (A), PVI4 ( ). Bulk V2O5 (+, after [10])... Figure I. Oxygen uptake by supported clusters and vanadium oxide. Samples were pre-reduced and re-oxidized at the temperatures indicated on the abscissa. Silica-supported polyoxometalates PVl ( ), PV3 (A), PVI4 ( ). Bulk V2O5 (+, after [10])...
Oxygen uptake stoichiometries of pre-reduced supported polyoxometalates... [Pg.340]

M.T. Pope and A. Muller (eds.) Polyoxometalates From Platonic Solids to... [Pg.463]

Predicted vacant polyoxometalates can be easily obtained by controlled hydrolyses, and are good reactive nucleophiles that can form a remarkable set of precursors for the design of large soluble molecules. [Pg.26]

M.T. Pope, A. Muller, Chemistry of polyoxometallates variations of an old theme with interdisciplinary relations. [Pg.254]

A. Muller, F. Peters, M.T. Pope, D. Gatteschini, Polyoxometallates very large clusters - nanoscale magnets. [Pg.254]


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Aromaticity polyoxometalates

Bringing the Components Together-Towards Prototype Polyoxometalate-based Functional Nanosystems

Building polyoxometalates

Catalytically active polyoxometalates

Complexes polyoxometalates

Dawson polyoxometalates

Energy polyoxometalates

Heterogeneous Polyoxometalate-Based Systems

Heterogenization of Polyoxometalates

Higher-Molecular-Weight Polyoxometallate Anions

Homogeneous epoxidation polyoxometallates

Hybrid material Composite polyoxometalate

Hybrid polyoxometalates

Hydrogen polyoxometalates

Isobutane polyoxometalates

Keggin structure polyoxometalates

Keggin-type polyoxometalates

Keggin-type polyoxometalates isobutane oxidation

Lacunary Polyoxometalates

Liquid Phase Oxidation Reactions Catalyzed by Polyoxometalates

Liquid polyoxometalate-catalyzed

Liquid-Phase Oxidations with Hydrogen Peroxide and Molecular Oxygen Catalyzed by Polyoxometalate-Based Compounds

Luminescence polyoxometalate materials

Luminescence polyoxometalates

Manganese-substituted polyoxometalate

Oxidation polyoxometalate catalyst

Oxidative polyoxometalate

Phosphonate Polyoxometallates

Photocatalyst polyoxometallates

Photocatalysts polyoxometallates

Photochemical, nano-ring formations in polyoxometalates

Pillars polyoxometallates

Polyanion Polyoxometalate

Polyoxometalate

Polyoxometalate

Polyoxometalate Crown Ether Complexes with Supramolecular cations

Polyoxometalate Keggin structure

Polyoxometalate Keggin-type

Polyoxometalate POM

Polyoxometalate Wells-Dawson-type

Polyoxometalate anions

Polyoxometalate as electrocatalyst

Polyoxometalate catalysis

Polyoxometalate catalyst

Polyoxometalate catalyzed reactions

Polyoxometalate chemistry

Polyoxometalate clusters

Polyoxometalate complexes

Polyoxometalate complexes, application

Polyoxometalate complexes, application catalysis

Polyoxometalate complexes, extending structural

Polyoxometalate composite

Polyoxometalate dendrimers

Polyoxometalate electrodes

Polyoxometalate epoxidation

Polyoxometalate immobilization

Polyoxometalate lacunary

Polyoxometalate lanthanide-containing

Polyoxometalate liquid phase oxidation

Polyoxometalate luminescence

Polyoxometalate oxidation with

Polyoxometalate perspectives

Polyoxometalate reviews

Polyoxometalate salt

Polyoxometalate sandwich-type

Polyoxometalate sulfoxide complex

Polyoxometalate-Based Compounds

Polyoxometalate-based functional

Polyoxometalate-based materials

Polyoxometalate-metal-organic frameworks

Polyoxometalate-pillared hydrotalcites

Polyoxometalate-supported transition metal

Polyoxometalates

Polyoxometalates

Polyoxometalates (Heteropolyacids)

Polyoxometalates (POM)

Polyoxometalates Binodal Orbital Aromaticity

Polyoxometalates Catalysts for Sustainable Oxidations and Energy Applications

Polyoxometalates agents

Polyoxometalates alcohols

Polyoxometalates alkanes

Polyoxometalates alkenes

Polyoxometalates applications

Polyoxometalates catalyst features

Polyoxometalates catalysts

Polyoxometalates catalysts, structure

Polyoxometalates catalytic oxidation

Polyoxometalates cations

Polyoxometalates characterized

Polyoxometalates crown ether complexes with supramolecular

Polyoxometalates defined

Polyoxometalates dehydrogenation

Polyoxometalates discovery

Polyoxometalates electrostatic interactions

Polyoxometalates encapsulation

Polyoxometalates evolution

Polyoxometalates excited state energies

Polyoxometalates heterogenization

Polyoxometalates hybrid material

Polyoxometalates hydrogen peroxide, activation

Polyoxometalates hydrophilic

Polyoxometalates isobutane oxidation

Polyoxometalates ketones

Polyoxometalates macroanions

Polyoxometalates oxidants

Polyoxometalates oxidation

Polyoxometalates oxidation catalyst, advantages

Polyoxometalates photocatalytic

Polyoxometalates photochromism

Polyoxometalates polyoxomolybdates

Polyoxometalates properties

Polyoxometalates quantum yields

Polyoxometalates redox potential

Polyoxometalates self-assembly process

Polyoxometalates supramolecular water clusters associated

Polyoxometalates surfactant encapsulated

Polyoxometalates synthesis

Polyoxometalates transition-metal complexes

Polyoxometalates types

Polyoxometallate

Polyoxometallate

Polyoxometallate anions

Polyoxometallate clusters

Polyoxometallate species

Polyoxometallates catalyzed olefin epoxidation

Polyoxometallates transition metal substitution

Properties of Polyoxometalates

Rare Earth Polyoxometalate Complexes

Ruthenium polyoxometalate

Sandwich polyoxometalates

Sandwich polyoxometalates structure

Sandwich-type polyoxometalate structure

Self-Assembly of Hydrophilic Polyoxometalate Macroanions in Dilute Solutions

Stability of polyoxometalates

Substitution polyoxometallates

Supported Keggin-type polyoxometalates

Supramolecular Features of Polyoxometalate-Supported Transition-Metal Complexes

Supramolecular Structures and Polyoxometalates

Supramolecular Water Clusters Associated with Polyoxometalates

Transition metal substituted polyoxometalate

Transition metal substituted polyoxometalate 4 with

Transition metal substituted polyoxometalates

Transition metal substituted polyoxometalates TMSP)

Transition metal substituted polyoxometallates

Tungsten polyoxometalate

Tungsten-based polyoxometalate

Tungsten-based polyoxometallates

Vacant polyoxometalates

Vanadium polyoxometalate

Vanadium-polyoxometalate catalyst

Water associated with polyoxometalates

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