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We have studied the intra- and intermolecular hydrogen transfer in a crystalline 1,1-diamino-2,2-dinitroethylene (DADNE) and 1,3,5-triamino-2,4,6-trinitrobenzene (TATB) by means of an embedded cluster method and density functional theory (DFT). We found that, even though both of these materials have similar amino- and nitro- functional groups and layered crystalline structures, there are important differences in the mechanisms of hydrogen transfer. In particular, our calculations suggest that the proton migration from an amino-group to a nitro-group of the samemolecule is a feasible process in TATB but not in DADNE. At the same time, we have found that no intermolecularhydrogen transfer occurs in either molecular crystal. These results imply that the activation of the decomposition reactions proceeds via different paths in these two materials. [ABSTRACT FROM AUTHOR]

A novel nanoporous material 12CaO·7Al2O3(C12A7) offers a possibility of incorporating large concentrations (>1021cm-3) of a wide range of extraframework anions inside its nanopores. We have investigated, both experimentally and theoretically, optical absorption associated with several types of such anions, including F-, OH-, O-, O2-, O2-, and O22-, and assigned their optical absorption bands. It is demonstrated that the chemical identity and concentration of extraframework anions can be controlled by an appropriate treatment of “as grown” C12A7. We also show that the position of the adsorption edge is, in turn, determined by the chemical identity of the extraframework species and can be varied in the range of ∼4−6 eV. We suggest that C12A7 is a unique host material, which can be used as a playground for studying negatively charged species that are unstable in other environments. [ABSTRACT FROM AUTHOR]