Uranyl ions structure

Leciejewicz J, Alcock NW, Kemp TJ (1995) Carboxylato Complexes of The Uranyl Ion Effects of Ligand Size and Coordinat. Geometry Upon Molecular and Crystal Structure. 82 43-84... 

Carbonate-fluor-apatite accommodates large quantities of trace elements, mainly uranium, which are potential luminescence centers. It has been proposed that uranium may occur in phosphorites in the following forms as a separate uraninite phase as an adsorbed or structurally incorporated uranyl ion as a dominantly replacement for Ca +, to be structurally incorporated... 

Mizuoka, K., Ikeda, Y., Structural study on uranyl ion in l-butyl-3-methylimid-azolium nonafluorobutanesulfonate ionic liquid. Prog. Nucl. Ener., 47, 426-433, 2005. 

The study of composite cations encounters further problems for classical and conventional QM/MM simulations, as their lower symmetry makes the evaluation of interaction energy surfaces and analytical potential functions describing them difficult. In these cases the QMCF MD method provides an elegant solution as well, renouncing solute-solvent potential functions. This advantage could be well demonstrated in studies on the dimer of Hg(I) (39), the titanyl ion (64), and the uranyl ions of U(V) (65) and U(VI) (66). Whereas the Hg + ion still has a fairly regular hydration structure although with a quite peculiar shape, the... 

Batzar, K. Goldberg, D.E. Newman, L.J. Effect of P-diketone structure on the synergistic extraction of uranyl ion by tributylphosphate, J. Inorg. Nucl. Chem. 29 (1967) 1511-1518. 

Bums, J.H. 1983. Solvent-extraction complexes of the uranyl ion. 2. Crystal and molecular structures of cafe a-Bis( r-di- -butyl phosphato-0,0 ) dioxouranium(VI) and Bisfp-di-n-butyl phosphato-O, O )bis[(nitrato)(tn-n-butylphophine oxide) dioxouranium(VI)]. Inorg. Chem. 22 1174—1178. 

An analogue of the uranyl ion was discovered in the crystal structure of the air-stable compound PPh4 [UOCl4 NP( n-toluene)3 ] 987 [455], This complex (red crystalline solid) was prepared in CH2C12 by the replacement of a chlorine atom in PPh4 [UOCl5] via the formation of Me3SiCl (5.72) ... 

The emission spectra for uranyl-exchanged zeolites Y, mordenite and X all have differences but do show some fine structure and therefore resemble the solid state spectrum of uranyl acetate dihydrate. In fact, the spectrum of uranyl ions exchanged into sodium mordenite is very similar to that of the uranyl acetate dihydrate solid spectrum shown in Figure 1. Further support for our belief that some zeolites have a solution like environment and others have a solid like environment comes from the correlation between the crystallinity of these uranyl-exchanged zeolites and the appearance of some fine structure in the emission spectrum. We find no apparent correlation between this fine structure and the concentration of the uranyl ion in the zeolites even with a ten-fold change in the concentration of the uranyl ion. 

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