The reaction of Li2S and P2S5 with Li4[SnS4], a recently discovered, good Li(+) ion conductor, yields Li10SnP2S12, the thiostannate analogue of the record holder Li10GeP2S12 and the second compound of this class of superionic conductors with very high values of 7 mS/cm for the grain conductivity and 4 mS/cm for the total conductivity at 27 °C. The replacement of Ge by Sn should reduce the raw material cost by a factor of ~3.

A new lithium chalcogenidotetrelate, denoted as LiChT phase, with the elemental combination Li/Sn/S was synthesized as solvent-free and solvent-containing salts. We present and discuss syntheses, crystal structures, spectroscopic and thermal properties of the phases, as well as the Li + ion conductivity of Li 4 SnS 4 , which is formally related to the thio-LISICON parent system Li 4 GeS 4 , and thus represents the first member of a new thiostannate-LISICON family. The solvent-free title compound shows a very promising Li + ion conductivity of 7 × 10 −5 S·cm −1 at 20°C and 3 × 10S·cm −1 at 100°C, which is exceptionally high for a ternary compound. Activation energies for the lithium ion transport measured via impedance spectroscopy (0.41 eV) correlate reasonably well with the values (0.29 to 0.33 eV) deduced from ionic mobility studies by 7 Li solid-state NMR spectroscopy. NMR two-time correlation functions suggest the occurrence of an additional, geometrically more restricted, ultraslow-motional process down to 121 K.

This review summarizes the rich structural variety of copper and silver chalcogenide clusters with protecting ligand shells of phosphane and/or organic ligands that were generated starting out from silylated chalcogenide sources. This route turned out to be fairly selective and thus allows for the isolation of uniform, polynuclear to nanosized cluster molecules that can consist of only a few or up to hundreds of metal atoms, being bridged by the chalcogen atoms. However, all of these clusters are only kinetically stable with respect to the formation of the binary coinage metal chalcogen phases, but do not collapse into the solid M(2)E materials owing to the protection by bulky ligands on the surface. Upon a more detailed analysis of the development of the structural properties with the cluster size, one recognizes differences for the particular M/E combinations: whereas copper chalcogenide and silver selenide clusters show a clear tendency to approach structural patterns of the Cu(2)E bulk, most obvious for the Cu/Se combination, this is not visible for silver sulfide clusters, even not at the largest species with 490 silver and 302 sulfur atoms. Besides the discussion on the structures of title compounds, the review presents insight into the bonding properties, reactivity, thermal and photophysical properties. The latter can be interpreted in terms of the quantum confinement effect, thus demonstrating the clusters to be understood as intermediates between mononuclear complexes and binary bulk phases.

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Tailored light sources have greatly advanced technological and scientific progress by optimizing the emission spectrum or color and the emission characteristics. We demonstrate an efficient spectrally broadband and highly directional warm-white-light emitter based on a nonlinear process driven by a cheap, low-power continuous-wave infrared laser diode. The nonlinear medium is a specially designed amorphous material composed of symmetry-free, diamondoid-like cluster molecules that are readily obtained from ubiquitous resources. The visible part of the spectrum resembles the color of a tungsten-halogen lamp at 2900 kelvin while retaining the superior beam divergence of the driving laser. This approach of functionalizing energy-efficient state-of-the-art semiconductor lasers enables a technology complementary to light-emitting diodes for replacing incandescent white-light emitters in high-brilliance applications.