A mononuclear and two dinuclear heteroleptic Cu(I) complexes have been successfully prepared, using the chelating bis[(2-diphenylphosphino)phenyl] ether (DPEPhos) and pyrid-2´-yl-1H-1,2,3-triazole as N^N chelating ligands. They show good luminescence in solution at room temperature with long-lived excited states. Furthermore, bimolecular quenching experiments of these new complexes with the catalyst Ni(cyclam)Cl2 encourage the use of such compounds as photosensitizers for the photoreduction of carbon dioxide.

Temperature-dependent photoluminescence (PL) as well as thermoluminescence (TL) were studied in the Eu2+-doped hydrides LiMH3 (M = Sr, Ba) and the corresponding deuterides. Here, thermally stimulated luminescence was observed for the first time in a Eu2+-doped hydrides and deuterides. The onset temperature of quenching (T 95 %) and the quenching temperature (T 50 %) were determined from photoluminescence intensities, and the energy barrier for thermal quenching was estimated. Then, a scheme with the localization of divalent and trivalent lanthanide 4f and 5d levels for the example LiSrH3 was proposed. In deuterides, the quenching temperatures are slightly higher than in hydrides, which can be related to the influence of the different phonon frequencies. In the TL measurements we observed very shallow and intense TL glow peaks in all samples. We also used density functional methods in order to show qualitative trends for the stability of possible defects. The model calculation suggest that energetically favorable defects are the introduction of Eu2+ on a Sr2+ or Ba2+ site, the substitution of barium by strontium and vice versa, lithium and hydrogen vacancies and combinations, and possibly clusters thereof. The observed persistent luminescence for several minutes despite of the lack of intense traps at room temperature suggests that the material could in principle be promising for the design of long-lasting phosphors, if traps could be stabilized to be released at higher temperature.

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The structures of platinum cluster anions Pt 6 − −Pt 13 − have been investigated by trapped ion electron diffraction. Structures were assigned by comparing experimental and simulated scattering functions using candidate structures obtained by density functional theory computations, including spin−orbit coupling. We find a structural evolution from planar structures (Pt 6 − , Pt 7 − ) and amorphous-like structures (Pt 7 − −Pt 9 − ) to structures based on distorted tetrahedra (Pt 9 − −Pt 11 − ). Finally, Pt 12 − and Pt 13− are based on hcp fragments. While the structural parameters are well described by density functional theory computations for all clusters studied, the predicted lowest energy structure is found in the experiment only for Pt 6 − . For larger clusters, higher energy isomers are necessary to obtain a fit to the scattering data.