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Li+/H+ exchange was performed on Li5La3Nb2O12 using CH3COOH. After X-ray powder diffraction experiments to check the quality of Li5-xHxLa3Nb2O12, the chemical formulation was determined by thermogravimetric analysis coupled with mass spectrometry and flame photometry. The results showed unambiguously that the Li+/H+ exchange was not total and that some CH3COOH remained in the sample. Raman experiments revealed in addition that the organic contribution on the spectrum was due either to metal acetate or to ionic bond to the crystal. [ABSTRACT FROM AUTHOR]

Metalcyclopentadienyl complexes (MCp) + (M = Fe, Ru, Os) bound to the large polyaromatic hydrogenated hydrocarbon (PAH) C 96 H 24 used as a model for pristine graphene have been studied using a density functional theory (DFT) generalized gradient approximation (PBE functional) to reveal their structural features and dynamic behavior. The inter-ring haptotropic rearrangements (IRHRs) for these complexes were shown to occur via two transition states and one intermediate. The energy barriers of the η 6 ⇌ η 6 IRHRs of the (MCp) + unit were found to be 30, 27, and 29 kcal/mol for M = Fe, Ru, and Os, respectively. These values are significantly lower than the values found previously for smaller PAHs. Both polar and nonpolar solvents were found not to affect significantly the energy barrier heights. Investigated transition metal complexes could be used in general as catalysts in the design of novel derivatives or materials with promising properties. Metalcyclopentadienyl complexes (MCp) + of PAHs show catalytic properties mainly due to their structural details as well as their important characteristic of inter-ring haptotropic rearrangement. IRHRs take place usually by intramolecular mechanisms. During IRHRs, the ML n organometallic groups (OMGs) undergo shifting along the PAH plane and could coordinate additional reagents, which is important for catalysis. Large PAHs such as graphene, fullerenes, and nanotubes possess intrinsic anticancer activity, and numerous arene complexes of Ru and Os have been proven to have anticancer properties as well. We suppose that coordinating Ru or Os to very large PAHs could synergistically increase the anticancer activity of resulting complexes.

Three bimetallic platinum/silver nanoclusters, PtAg 20 (dtp) 12 ( 1 ), Pt 2 Ag 33 (dtp) 17 ( 2 ), and Pt 3 Ag 44 (dtp) 22 ( 3 ) (dtp: dipropyl dithiophosphate), with cluster electron counts of 8, 16, and 22, respectively, were produced via a one-phase coreduction method. Single-crystal X-ray structures reveal that their inner cores can be visualized as consisting of one, two, and three centered icosahedral Pt@Ag 12 units, respectively. In 2 and 3 , these units are vertex-sharing and are assembled linearly. Intriguingly, the 22-electron alloy ( 3 ) is isolobal to the linear triiodide anion, I 3 - , and represents the first example of a cluster made of three superatoms whose bonding characteristics are similar to those of a triatomic molecular species.

Li(+)/H(+) exchange was performed on Li5La3Nb2O12 using CH3COOH. After X-ray powder diffraction experiments to check the quality of Li5-xHxLa3Nb2O12, the chemical formulation was determined by thermogravimetric analysis coupled with mass spectrometry and flame photometry. The results showed unambiguously that the Li(+)/H(+) exchange was not total and that some CH3COOH remained in the sample. Raman experiments revealed in addition that the organic contribution on the spectrum was due either to metal acetate or to ionic bond to the crystal.