The crystal structure of bergenite, ideally Ca2Ba4[(UO2)3O2(PO4)2]3(H2O)16, monoclinic, space group P21/c, a 10.092(1), b 17.245(2), c 17.355(2) Å, 113.678(2)°, V 2766.2(3) Å3, Z = 2, Dcalc 4.82 g/cm3, was solved by direct methods and refined by full-matrix least-squares techniques on the basis of F2 to agreement indices R1 of 5.0% calculated for 4118 unique observed reflections (|Fo| ≥ 4 F), a...

Two mononuclear U02(VI) complexes of the general formula [(HL)U02(OH2)2] О.бШО, where L is a pentadentate N2O3 asymmetric Schiff base ligand, were synthesized and used as ligands for further coordination of either Cu(II) or Ni(II) ions. The U02(VI) ion occupies the outer O2O sites of the ligands, thus leaving the inner N2O2 sites of the ligands vacant for further coordina­ tion. Different types...

In this paper, NMR and QTAIM analysis for three substituted of T2SA complex was investigated in the gas and four solvents at DFT level. Intermolecular O–H…N hydrogen bonds between 1,2,4,5-Tetrazine and Sulphurous acids enhance the stability of complex.1,2,4,5-Tetrazine is a highly reactive diene for [4+2] inverse-Diels–Alder cycloaddition processes and an excellent precursor to attain the pyrid...

The geometries, relative energies and spectroscopic properties of a range of α-isosaccharinate complexes of uranyl(VI) are studied computationally using ground state and time-dependent density functional theory. The effect of pH is accommodated by varying the number of water and hydroxide ligands accompanying isosaccharinate in the equatorial plane of the uranyl unit. For 1 : 1 complexes, the c...

The electronic spectra of uranyl(VI) coordinated with four equatorial halide ligands, [UO2X4]2- (X = F, Cl, Br, and I), have been calculated at the all-electron level using the multiconfigurational CASPT2 method, with spin-orbit coupling included through the variational-perturbational method. The halide-to-uranyl charge-transfer states were taken into account in the calculation by including lig...

The title compound, [UO(2)(C(14)H(8)O(5))(H(2)O)](n), is a polymeric UO(2) complex bridged by 4,4'-oxydibenzoate ligands. One carboxyl-ate group of the bridging ligand chelates a uranyl cation while the other carboxyl-ate group of the ligand bridges two other two uranyl cations, forming a double-chain polymeric structure. The central U(VI) atom is seven-coordin-ated in a distorted UO(7) penta-g...

Using a scalar relativistic all-electron density functional method, we studied uranium(VI) complexation with benzoic acid and its derivatives in aqueous solution as models of uranyl humates. We explored monodentate, bidentate, and chelate coordination of various isomers of methyl and hydroxyl substituted benzoic acid ligands. Monodentate complexes were determined to be energetically preferred a...

New tripodal gem-(bis-phosphonates) uranophiles were discovered by a screening method that allowed for the selection of ligands with strong uranyl-binding properties in a convenient microtiter-plate format. The method is based on competitive uranium binding by using Sulfochlorophenol S as chromogenic chelate. This dye compound was found to present high uranyl complexation properties and allowed...

The synthesis of the mono-uranyl complex [UO(2)(THF)(H(2)L(Me))] of a ditopic Schiff-base pyrrole macrocycle is described and is shown to adopt a Pacman wedge-shaped structure in which the uranyl dication is desymmetrised and sits solely in one N(4)-donor compartment to leave the other vacant. While investigating the mechanism of the previously reported, base-initiated, reductive silylation che...

A comprehensive study of the complexes A4[U(NCS)8] (A = Cs, Et4N, (n)Bu4N) and A3[UO2(NCS)5] (A = Cs, Et4N) is described, with the crystal structures of [(n)Bu4N]4[U(NCS)8]·2MeCN and Cs3[UO2(NCS)5]·O0.5 reported. The magnetic properties of square antiprismatic Cs4[U(NCS)8] and cubic [Et4N]4[U(NCS)8] have been probed by SQUID magnetometry. The geometry has an important impact on the low-temperat...