Zwei unabhängige Verfahren (Fällung aus wäßriger Lösung und Festkörperreaktion) zur Darstellung vom vorher unbekannten Na5AlF2(PO4)2 wurden optimiert. Die Kristallstruktur wurde mit Diffraktometerdaten aufgeklärt (P3, a = b = 10,483(1), c = 6,607(1) Å, MoKα, 1080 unabhängige Reflexe, Rw = 0,025). PO4‐Tetraeder und AlO4F2‐„Oktaeder”︁ sind über gemeinsame Ecken zu einem zweidimensional ausgedehnten Heteropolyanion verknüpft. Natrium befindet sich in miteinander verbundenen Röhren des [AlF2(PO4)2]‐Teils der Struktur. Die aufgrund der Strukturmerkmale zu erwartende Natriumionenleitfähigkeit wird experimentell bestätigt.

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The microstructures of five internally oxidized Ag-Sn-In materials were investigated using ion polishing, field emission scanning electron microscopy and electron backscatter diffraction. The ion polished sections showed a subtle material contrast in the oxide particles that could be attributed to different oxide phases generated during internal oxidation. The phases could be identified as tetragonal SnO 2 that surrounds the cubic In 2 O 3 core of the combined oxide particles. It is shown that In 2 O 3 exhibits an orientation relationship to the Ag matrix and for SnO 2 and Ag another orientation relationship is likely. Interrupted internal oxidation experiments were applied to identify the growth mechanism of the oxide particles. A consistent view on the role of In during the internal oxidation of Ag-Sn-In alloys as heterogeneous nucleation agent of SnO 2 is presented.

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The X-ray powder diffraction data for δ-Na2Si2O5 are reported. The sample was prepared from water glass solution applied to pressed powder tablets of finely ground quartz using a heating program with a maximal temperature of 700 °C. The crystallographic data for δ-disilicate obtained from a Rietveld analysis are: space group P21/n, a=8.3818(4) Å, b=12.0726(5) Å, c=4.8455(2) Å, β=90.303(5)°, V=490.31 Å3, Z=4, and Dcalc.=2.468 g/cm3.