Mono actinide

Anderson RF, Bacon MP, Brewer PG (1982) Elevated concentrations of actinides in Mono Lake. Science 216 514-516... 

These compounds have a metallic character or are intermetallics. Actinide carbides (mono-, sesqui-, dicarbides) are prepared by carboreduction of the oxides ... 

With regards to actinides, Summerscales et al. [105] have also reported the reductive disproportionation of C02 to carbonate and squarate products, using COTR/ CpR mixed-sandwich U(III) complexes (COT = cyclooctatriene, Cp = cyclopenta-dienyl, R = Si Pr3, R = H, Me). U(III) systems have been shown previously to reduce C02 to a linear Tl -O-coordinated mono-anion [63], and to doubly reduce to give O2- salts plus CO [75, 76]. In this case, the reactions can be considered... 

Monochromatic organic light-emitting diodes light-emitting electrochemical cells, 12, 175 with organometallic emitters, 12, 158 Monocyclic arenes, in Ru and Os compounds, 6, 466 Mono(cyclooctatetraenyl) actinide(IV) compounds, preparation, 4, 227... 

Mono(organo)nickel compounds, via oxidative addition, 8, 44 Monoorganotin hydroxides, preparation, 3, 850 Monoorganotin oxides, preparation, 3, 850 Mono(pentamethylcyclopentadienyl) actinide(IV) compounds, reactions, 4, 207 Mono(pentamethylcyclopentadienyl) lanthanide(III) compounds, synthesis and characteristics, 4, 66 Mono(pentamethylcyclopentadienyl) uranium(IV) sulfido complex, synthesis, 4, 207-208 Mono(phenoxy-aldehyde) trichlorides, with Zr(IV),... 

Pentamethylcyclopentadienyl complexes CpjAnX, 4, 207 Cp AnX2 and Cp AnX, 4, 206 Cp MX compounds, 4, 62 with iridium amidinates, 7, 366 mono(Cp ) actinide(IV) compounds, 4, 207 with Ni-C cr-bonded ligands, 8, 108-109 with rhodium, 7, 152 with ruthenium, 6, 632 tris(Cp ) actinide(IV) compounds, 4, 219 with zirconium amidinates, 12, 730 l, 2, 3, 4, 5 -Pentamethyl-l-formylruthenocene, preparation, 6, 643... 

O. Vogt and K. Mattenberger, Magnetic measurements on rare earth and actinide monopnictides and mono-chalcogenides 301... 

There will undoubtedly be many new catalysts described in the near future. In particular, we anticipate that later transition-metal complexes will play a much larger role in this type of chemistry. Although bis-Cp complexes of Groups 3 and 4, the lanthanides, and the actinides have shown exceptional activity and thus far have dominated reported investigations on catalytic homodehydrocoupling, it is most unlikely that they are unique in this property. It is to be expected that other classes of complexes, such as mono-Cp and -rj -alkyl complexes of these elements, will also be active. Other directions for future evolution are the development of catalysts that are air stable, that are tolerant of more functionalities on substrates, and that are more easily manipulated. 

Bis(pentametiiylcyclopentadienyl)actinide(IV) mono- and dialkyl complexes are readily prepared from Cp 2 Cl2. A rather large number of alkyl groups have been employed, and compounds of this class are generally prepared by metathesis (equation 59). In the solid state, complexes of formula Cp 2" n 2 adopt a pseudotetrahedral coordination geometry about the actinide metal. A neutron diffraction study of the thorium neopentyl complex Cp 2Th(CH2-t-Bu)2 also revealed agostic Th-H-C interactions with the q -CH bonds. ... 

Explain the trends in the magnitudes of the log ,/f, values for the formation of the mono pentane-2.4-dionate comple.xes of lanthanide and actinide ions shown in Table 5.2. Consider the variation across the lanthanide series, the variation across the actinide series, and the differences between the two series. 

Hydroxides. Pure and mixed metal actinide hydroxides have been studied for their potential utility in nuclear fuel processing. At the other end of the nuclear cycle, the hydroxides are important in spent fuel aging and dissolution, and environmental contamination. Tetravalent actinides hydrolyze readily, with Th more resistant and Pu more likely to undergo hydrolysis than and Np. All of these ions hydrolyze in a stepwise marmer to yield monomeric products of formula An(OH) with = 1,2,3 and 4, in addition to a number of polymeric species. The most prevalent and well characterized are the mono- and tetra-hydroxides, An(OH) and An(OH)4. Characterization of isolated bis and tri-hydroxides is frustrated by the propensity of hydroxide to bridge actinide centers to yield polymers. For example, for thorium, other hydroxides include the dimers. 

Sulfates and sulfites. Mono- and bis-sulfate complexes of actinyl ions, An02S04 and An02(S04)2 , are generally prepared from acidic solutions. The geometry about the actinide metal center is pentagonal biypyramidal from actinyl, sulfato, and aquo oxygen atoms. A tris(sulfato) complex has been reported, but it is very weak if it does exist. Ternary hydroxo, sulfato complexes have been reported for uranyl, but they have not been structurally characterized. 

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