Bare uranyl tetrafluoride (UO 2 F 4 2À) and its solvation complexes by one and two water or acetonitrile molecules have been observed in the gas phase using electrospray ionization and investigated by photoelectron spectroscopy and ab initio calculations. The isolated UO 2 F 4 2À dianion is found to be electronically stable with an adiabatic electron binding energy of 1.10 AE 0.05 eV and a repulsive Coulomb barrier of $2 eV. Photoelectron spectra of UO 2 F 4 2À display congested features due to detachment from U-O bonding orbitals and F 2p lone pairs. Solvated complexes by H 2 O and CH 3 CN, UO 2 F 4 (H 2 O) n 2À and UO 2 F 4 (CH 3 CN) n 2À (n ¼ 1, 2), are also observed and their photoelectron spectra are similar to those of the bare UO 2 F 4 2À dianion, suggesting that the solvent molecules are coordinated to the outer sphere of UO 2 F 4 2À with relatively weak interactions between the solvent molecules and the dianion core. Both DFT and CCSD(T) calculations are performed on UO 2 F 4 2À and its solvated species to understand the electronic structure of the dianion core and solute-solvent interactions. The strong U-F interactions with partial (d-p)p bonding are shown to weaken the U]O bonds in the [O]U]O] 2+ unit. Each H atom in the water molecules forms a H-bond to a F atom in the equatorial plane of UO 2 F 4 2À , while each CH 3 CN molecule forms three H-bonds to two F ligands and one axial oxygen.

We report a practical approach, the first of its kind, to construct nanoscale UiO-type metal-organic framework (Mi-UiO-66 and Mi-UiO-67) fluorescent probes for the detection of Cys and GSH. They showed high sensitivity (10(-11) M) and selectivity for Cys and GSH, and their fluorescence imaging of Cys and GSH in living cells was well demonstrated.

Actinyl-tricarbonato anions [(AnO)(CO)] (An = U-Cm) in various environments were investigated using theoretical approaches of quantum-mechanics, molecular-mechanics and cluster-models. Cations and solvent molecules in the 2 coordination sphere affect the equatorial An←O bonds more than the axial An[triple bond, length as m-dash]O bonds. Common actinide contraction is found for calculated and experimental axial bond lengths of U toPu, though no longer for Pu toCm. The tendency of U to Pu forming actinyl(vi) species dwindles away toward Cm, which already features the preferred An/Ln oxidation state of the later actinides and all lanthanides. The well known change from d-type to typical U-Pu-Cm type and then to f-type behavior is labeled as the plutonium turn, a phenomenon that is caused by f-orbital energy-decrease and f-orbital localization with increase of both nuclear charge and oxidation state, and a non-linear variation of effective f-electron population across the actinide series. Both orbital and configuration mixing and occupation of antibonding 5f type orbitals increase, weakening the AnO bonds and reducing the highest possible oxidation states of the later actinides.

Density functional theory calculations have been performed to investigate the detailed mechanism of the carbonyl hydrogenation catalyzed by the first well-defined bifunctional iron catalyst. The catalytic reaction proceeds by hydrogen transfer and dihydrogen activation. The hydrogen transfer reaction occurs via the bifunctional mechanism in which the two hydrogen atoms attached on the Fe and O of the catalyst are transferred to the oxygen and carbon atom of the carbonyl compound concertedly. Both the alcohol-mediated and nonalcohol-mediated dihydrogen activation processes are explored.