Crown ether compounds of actinide bis(β-diketonate). Synthesis, characterization and molecular structures of [UO2(TTA)2H2O]2(benzo-15,crown-5) (1) and [UO2(TTA)2(μ-H2O)]2(H2O)2(dibenzo-18,crown-6) (2)

Bis(1,3-diphenylpropane-1,3-dionato-κ2O,O′)dioxo(triphenylphosphine oxide-κO)uranium(VI)

“…1. Selected bond distances and angles are listed in Table 1 (Taylor & McLaren, 1979;Kannan, Venugopal, Pillai, Droege, Barnes & Schlmber, 1996;Kannan et al, , 2000Kannan et al, , 2001b. The U-O(P) phosphine oxide distance [2.375 (4) Å] is comparable with those reported earlier for uranyl bis(β-diketone)-phosphine adducts (Taylor & McLaren, 1979;Lu et al, 1977;Kannan et al 2001a).…”

“…Four O atoms of DBM and one O atom of phosphine oxide form a planar pentagon and two uranyl O atoms occupy the apices. The average of UÐO uranyl [1.767 (4) A Ê ] and UÐO DBM [2.365 (4) A Ê ] distances are within the accepted ranges (Taylor & McLaren, 1979;Kannan, Venugopal, Pillai, Droege, Barnes & Schlmber, 1996;Kannan et al, , 2000Kannan et al, , 2001b. The UÐ O(P) phosphine oxide distance [2.375 (4) A Ê ] is comparable with those reported earlier for uranyl bis(-diketone)±phosphine adducts (Taylor & McLaren, 1979;Lu et al, 1977;Kannan et al, 2001a).…”

Density functional theory (DFT) calculations of VI/V reduction potentials of uranyl coordination complexes in non-aqueous solutions

“…However, this picture is somewhat complicated as a crown ether molecule is present in the crystal structure which bridges two [UO 2 (ttfacac) 2 (H 2 O)] units. 81 Gagliardi et al 82 have studied the structural isomerism of a plutonyl(VI) complex of 'ttfacac' ligand. However, there was no mono-dentate ligand coordinated to the plutonyl ion in the [PuO 2 (tfacac) 2 ] complex.…”

Aquadioxidobis(pentane-2,4-dionato)uranium(VI) pyrazine solvate

“…The deviations of the O atoms of the acac and of the H 2 O from the equatorial plane (O3, O4, O5, O6 and O7) are within 0.02 Å. The U1-O acac bond lengths are longer than the U1-O uranyl distances and are shorter than the U1 (Kannan et al, 2001).…”

“…For related structures, see: Alcock et al (1984; ; Borkowski & Cahill (2004); Huuskonen et al (2007); Kannan et al (2001); Takao & Ikeda (2008). = 86.130 (6) V = 928.0 (5) Å 3 Z = 2 Mo K radiation = 8.78 mm À1 T = 299 K 0.22 Â 0.14 Â 0.06 mm…”