Polyoxomolybdates

Polyoxoacids, defined, 41 117,118 Polyoxometalates defined,41 117,118 transition-metal-substituted, 41 224-225 Polyoxomolybdates, 41 193 Polyoxotetramelhyleneglycol, synthesis, 41 156-157... 

More recently, some other compounds containing polyoxometallates coordinated to Bi were reported by U. Kortz et al., who investigated the interactions of amino acids with polyoxomolybdates in the presence of inter alia Bi +-ions [55,56]. A series of ionic compoimds with anions of the general formula [XM06O21 (amino acid)3] (X = As , Sb , Bi ) were prepared. In case of the bismuth derivatives the amino acids HOOC(CH2) NH2 (n = 1, 2, 3) and L-HOOCCH[(CH2)4NH2]NH2 were reacted with Na2Mo04, Bi203 and KCl in an aqueous medium (Eq. 8). 

In the reoxidation of heteropolyanions, reduced forms of polyoxomolybdates and polyoxovanadates are stable and hardly reoxidized by molecular oxygen, whereas polyoxotungstates undergo facile reoxidation (257). 

Figure 9.24 The polyoxomolybdate nanocluster [P]2(Mo204(MeCO ) 30l42 (P = (Mo)Mo502i (I I20)6 6 ) that behaves as an artificial cell, showing the pore opening in the centre (reprinted from [21] with permission of Elsevier).

Keywords antifreeze protein P-helix C6o fullerene hydration hydrophilic surface explicit water model ice crystal icosahedral water cluster polyoxomolybdate colloid... 

The icosahedral cluster model1,2 offers a structure on which large molecules can be mapped in order to investigate their interaction with water within a three-dimensional hydrogen-bonded network, and here offers new insights into the ways fullerene and polyoxomolybdate molecules interact with water in aqueous solution. 

Figure 6. The polyoxomolybdate Moi54 supercluster showing how 20 nano-wheels may form one of the 12 pentagons and how 24 nanowheels may form one of 80 distorted hexagons. The short links are the Mo—Mo linkages (—1.59 nm) as in Figure 5 and the long links (—12.36 nm) along the octamers are close to the major peak found in the SAXS experimental data (12.9 nm).17...

Cazacu A, Mihai S, Nasr G, van der Mahon E, Lee A, Meffre A, Barboiu M (2010) Lipophilic polyoxomolybdate nanocapsules in constitutional dynamic hybrid materials. Inorg Chim Acta 363 4214-4219... 

It is also possible to make a variety of polyoxomolybdate species containing NO ligands.68 The NO source is generally Me2C=NOH. 

GeWi204o] and [GeMoi204o] anions are stable in acid solution, however, when the pH value reaches 5.3 or 7.3, they decompose to Ge02 and polyoxomolybdate or polyoxotungsten. 

Increasing numbers of extremely large polyoxomolybdate anions, with ring-shaped and hollow stmctures have been described. These contain mixed-valence polymolybdate anions that are constmcted using common building blocks containing M02, Moe, and M08 units, some of which have no independent stable existence. This area of cluster molybdenum chemistry has been extensively reviewed. 

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