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Synthetic 2-, 3-, 4- and 6-monophosphate derivatives of methyl α- d -mannopyranosides, the 4-, 6- and 7-monophosphate derivatives of methyl l - glycero -α- d - manno- heptopyranosides and the corresponding phosphoethanolamine derivatives and a 6,7-cyclic phosphate analogue of methyl l - glycero -α- d - manno- heptopyranoside were used to study phosphate migration and hydrolysis when subjected to strong alkaline conditions (4 M KOH, 120 °C, 18 h). The resulting products were analyzed by 1 H NMR spectroscopy and electrospray mass spectrometry. It was found that phosphate substituents were stable under these conditions and neither migration nor hydrolysis was observed except for the heptose 7-phosphate, which gave a substantial amount of phosphate hydrolysis. In phosphoethanolamine-substituted compounds migration to adjacent positions with concomitant loss of ethanolamine was found together with hydrolysis.

Diamido-difluoro-tin Sn(ND 2 ) 2 F 2 can be produced by ammonolysis from (NH 4 ) 2 SnF 6 at 633 K. The compound is a product formed from Sn(ND 3 ) 2 F 4 during the ammonolysis reaction. Sn(ND 2 ) 2 F 2 isostructural with Sn(NH 2 ) 2 F 2 crystallizes in space group C2/m with lattice constants a = 1072.92(7), b = 325.97(1) pm, c = 505.79(4) pm and β = 105.713(6) ° (V = 170.28(1) ·10 6 pm 3 ) containing two formula units per unit cell. Data refinement by the Rietveld method of neutron time-of-flight data collected at POLARIS yields a weighted profile R-value R wp = 0.022. Tin is octahedrally coordinated by two fluorine atoms and four amido groups. The octahedra are connected to one-dimensional chains by edge sharing. The ND 2 groups are in the bridging position whilst the fluorine atoms are terminal. Nearly linear (175.2(4) °) and angular (134.35(8) °) N-D···F hydrogen linkages connect the chains.

The nitridation of an amorphous ZrO2 ·H2O precursor with gaseous ammonia has been studied by in situ X-ray powder diffraction (temperature range 25−1100 °C), electron diffraction (temperature range...

A powder of the composition 40 mol-% Er2O3 and 60 mol-% ZrO2 has been prepared. The anion deficient fluorite related compound Zr3Er4O12 [R\bar{3}: a = 971.79(7) pm and c = 907.976(0) pm] was produced. This precursor was treated with gaseous ammonia at temperatures between 25 and 1200 °C. The reaction was followed in situ by X-ray diffraction in a high temperature reaction chamber under a constant flow of ammonia. The nitridation of Zr3Er4O12 led to a nitride oxide of the solid-solution-type with an apparent composition Zr0.43Er0.57O1.07N0.43 The compound crystallizes isostructural to bixbyite due to vacancy ordering [Ia\bar{3}: a = 1036.37(4) pm]. The reoxidation of the nitride oxide was monitored in DTA/TG experiments exhibiting an almost complete reoxidation to the starting composition except for some inclusions of dinitrogen.

The nitridation of Zr50Sc12O118 (Zr0.807Sc0.193O1.90), an anion deficient fluorite related compound, with ammonia yields at 1100 °C a green product with composition Zr1.613Sc0.387O1.387N1.613. This compound crystallizes cubic in space group (a = 1007.8(5) pm) and is isostructural to Bixbyite with statistical distribution of Zr/Sc at the cation and of O/N at the anion sites. These are the results of Rietveld refinements from a powder neutron diffraction experiment. If Zr3Sc4O12 (Zr0.429Sc0.571O1.714), an educt with another Zr/Sc ratio, is nitridated with ammonia the reaction path shows again the formation of a compound with a bixbyite structure, but finally at 1200 °C a red nitride with the composition Zr3Sc4N8 (Zr0.375Sc0.5N) is formed. This compound has a cation deficient NaCl type structure (space group is ) with a = 452.8(1) pm. Neutron diffraction revealed again no ordering on the cation sites. Both compounds show an unperturbed N≡N stretching frequency in their Raman spectrum at 2327 cm−1. Zr3Sc4N8 exhibits at 1552 cm−1 a second sharp line which was assigned to a N22− moiety.

Colorless plates of Zr 50 Sc 12 O 118 have been produced by firing zirconia with scandia at temperatures above 1000 °C and cooling slowly. The resulting crystals were heavily twinned. The unit cell is rhombohedral with space group R 3 and lattice constants a =1981.70(5) and c =1805.59(6) pm. The structure is fluorite-related anion-deficient. Within the cell there are 18 vacancies on oxygen positions. A further neutron time of flight study revealed an almost statistical distribution of Zr and Sc on the cation positions.