Quantum chemistry of OsCl photoaquation products and the reaction scheme.

Quantum chemical calculations (CASSCF and XMCQDPT level of theory, IMCP-SR1 and SBKJC basis sets) of the structures and electronic absorption spectra of the OsIVCl5(H2O)- and OsIVCl5(OH)2- complexes, which are the products of OsIVCl62- photoaquation, were performed. The satisfactory agreement between the experimental and calculated spectra was achieved using both triplet and quintet manifolds. The dissociation of the aquacomplex with the formation of the hydroxocomplex was explained by the thermochemical data.

Magnetic field effect on ion pair dynamics upon bimolecular photoinduced electron transfer in solution.

The dynamics of the ion pairs produced upon fluorescence quenching of the electron donor 9,10-dimethylanthracene (DMeA) by phthalonitrile have been investigated in acetonitrile and tetrahydrofuran using transient absorption spectroscopy. Charge recombination to both the neutral ground state and the triplet excited state of DMeA is observed in both solvents. The relative efficiency of the triplet recombination pathway decreases substantially in the presence of an external magnetic field.

Short-lived intermediates in photochemistry of an OsCl complex in aqueous solutions.

Two mechanisms of OsCl photolysis were studied by means of quantum chemical calculations in gas and aqueous phases. The difference between these mechanisms is in the nature of the possible Os(iv) key intermediates (KI). According to calculations, the intermediate is an OsCl complex of square pyramidal coordination geometry.

Primary photophysical and photochemical processes for hexachloroosmate(iv) in aqueous solution.

The photoaquation of the OsCl complex was studied by means of stationary photolysis, nanosecond laser flash photolysis and ultrafast kinetic spectroscopy. The OsCl(OH) complex was found to be the only reaction product. The quantum yield of photoaquation is rather low and wavelength-dependent.

Thoron progeny size distribution in monazite storage facility.

Field experiments in the atmosphere of monazite warehouses with a high content of (220)Rn progeny concentration were conducted. Size distribution of aerosol particles was measured with the combined use of diffusion battery with varied capture elements and cascade impactor. Four (212)Pb aerosol modes were detected-three in the ultrafine region (aerosol median thermodynamic diameters ∼0.