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The thermodynamic stability of the [HCB11Cl11]–salts of the cationic one‐electron oxidizers [NO]+and [O2]+was estimated by Born–Haber–Fajans cycles based on quantum‐chemical calculations and lattice enthalpy estimations. [NO][HCB11Cl11] is predicted to be a stable compound, whereas [O2][HCB11Cl11] should decompose into O2and the HCB11Cl11·radical. Consequently, [NO][HCB11Cl11] can be prepared by metathesis reaction from Na[HCB11Cl11] and [NO][BF4] in liquid sulfur dioxide, while attempts to synthesize [O2][HCB11Cl11] failed. [NO][HCB11Cl11] has been fully characterized by NMR and vibrational spectroscopy. Single crystals of [NO][HCB11Cl11]·SO2were obtained from liquid sulfur dioxide solution. The crystal structure determination revealed several intermolecular cation–anion contacts, which are significantly shorter than the sum of the van der Waals radii of the respective atoms. [NO][HCB11Cl11] reacts with white phosphorus in CH2Cl2solution to give yellow‐orange [P4NO][HCB11Cl11] containing the [P4NO]+cation. An in‐situNMR spectroscopic study indicates the presence of the homopolyatomic phosphorus cation [P9]+in the reaction mixture.

Foreshadowing a new selenium modification …︁?Upon treatment of red, amorphous selenium with the silver salts of two large weakly coordinating anions (WCA), the thermodynamically driven formation of [Ag2Se12]2+occurred. The structure of the dication is an unprecedented D3d‐symmetric 14‐vertex cage built from six six‐membered rings in a boat conformation that includes a weak argentophilic Ag–Ag bond.

Deutet sich hier eine neue Selenmodifikation an…︁?Bei der Reaktion von rotem amorphem Selen mit Silbersalzen zweier großer, schwach koordinierender Anionen wurde die thermodynamisch begünstigte Bildung von [Ag2Se12]2+beobachtet. Die Struktur des Dikations ist ein neuartiger D3d‐symmetrischer 14‐eckiger Käfig, aufgebaut aus sechs sechsgliedrigen Ringen in Bootkonformation, der eine schwach argentophile Ag‐Ag‐Bindung enthält.

An appealing couple: The unprecedented insertion of the nitrosonium cation into a tetrahedral edge of white phosphorus forms the highly reactive [P4NO]+cation (see picture). The synthesis, characterization, and applications are discussed, and NO2[Al(OC(CF3)3)4] is presented as an easily synthesized oxidant.

Ein reizvolles Paar: Das Nitrosonium‐Kation reagiert mit einer Tetraederkante des weißen Phosphors unter Bildung des hochreaktiven, neuartigen Kations [P4NO]+(siehe Bild). Synthese, Charakterisierung und Anwendungen werden diskutiert und mit NO2[Al(OC(CF3)3)4] ein einfach zu synthetisierendes Oxidationsmittel vorgestellt.

The flow in a floating element flowmeter (Rotameter) has been previously studied with laser Doppler anemometry (LDA) and computational fluid dynamics (CFD). Although there was good agreement between experimental and numerical results in general, some discrepancies remained in the separation region after the float. This Technical Note extends the investigations to consider rotation of the float, which was not taken into account in earlier computations, in an effort to explain the observed discrepancies between experimental and numerical results. The impact on the velocity field in the main stream direction increases at higher angular velocities of the float. Further refinement of the computational grid shows that the number of nodes has been sufficient.