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Guanylurea dicyanamide, [(H2N)C(&dbd;O)NHC(NH2)2][N(C&tbd1;N)2], has been synthesized by ion exchange reaction in aqueous solution and structurally characterized by single-crystal X-ray diffraction (C2/c, a = 2249.0(5) pm, b = 483.9(1) pm, c = 1382.4(3) pm, β = 99.49(3)°, V = 1483.8(5) × 10⁶ pm³, T = 130 K). The thermal behavior of the molecular salt has been studied by thermal analysis, temperature-programmed X-ray powder diffraction, FTIR spectroscopy, and mass spectrometry between room temperature and 823 K. The results were interpreted on a molecular level in terms of a sequence of thermally induced addition, cyclization, and elimination reactions. As a consequence, melamine (2,4,6-triamino-1,3,5-triazine) is formed with concomitant loss of HNCO. Further condensation of melamine yields the prototypic CNx precursor melem (2,6,10-triamino-s-heptazine, C6N7(NH2)3), which alongside varying amounts of directly formed CNxHy material transforms into layered CNxHy phases without significant integration of oxygen into the core framework owing to the evaporation of HNCO. Thus, further evidence can be added to melamine and its condensation product melem acting as “key intermediates” in the synthetic pathway toward graphitic CNxHy materials, whose exact constitution is still a point at issue. Due to the characteristic formation process and hydrogen content a close relationship with the polymer melon is evident. In particular, the thermal transformation of guanylurea dicyanamide clearly demonstrates that the formation of volatile compounds such as HNCO during thermal decomposition may render a large variety of previously not considered molecular compounds suitable CNx precursors despite the presence of oxygen in the starting material.

(P4S3).(Bl3) was prepared and characterized by X-ray Powder Diffraction, 31P MAS NMR, IR and Raman Spectroscopy. Density functional calculations (B3LYP) were carried out.

Fluorescence emission was investigated in a series of Ba2−xEuxSi5N8compounds. Two maxima corresponding to the two crystallographic Eu2+sites are observed. Excitation with intense laser light at 1.047μm reveals strong fluorescence emission at ∼600nm due to two-photon-excitation. In Ba1.89Eu0.11Si5N8the long lasting luminescence was studied. The emission peaking at about 590nm has been observed in the dark with the naked eye even 15min after removal of the activating lamp. This effect is due to the recombination of holes and traps consisting of nitrogen vacancies formed by reducing synthesis conditions. The maximum emission was observed at −7°C.

K5H(CN2)3wurde phasenrein durch Umsetzung von KHCN2mit metallischem Kalium in flüssigem Ammoniak sowie auch durch Reaktion von KNH2mit Melamin C3N3(NH2)3bei 320 °C synthetisiert. Die Kristallstruktur wurde mit Pulver‐ und Einkristallmethoden bestimmt: K5H(CN2)3, Raumgruppe Im3m, a = 795,68(7) pm, Z = 2, R1 = 0,025, wR2 = 0,0438. K5H(CN2)3ist im Festkörper aus K+und CN22‐Einheiten mit der Symmetrie D∞haufgebaut. Nach 1H‐ und 13C‐Festkörper‐NMR‐Untersuchungen, temperaturabhängiger Impedanzspektroskopie sowie FTIR‐Untersuchungen sind die Protonen nur schwach an die CN22–‐Ionen gebunden. Die Protonenleitfähigkeit von K5H(CN2)3steigt bei 70 °C sprunghaft an.

Coarse crystalline Ag3(PO2NH)3(1) and K3(PO2NH)3(2) are obtained by addition of an aqueous solution of AgNO3to an acidified solution of Na3(PO2NH)3· 4H2O and by diffusion controlled addition of ethanol to a solution of K3(PO2NH)3in water, respectively. The crystal structures of 1 and 2 have been determined by single crystal X-ray methods (Ag3(PO2NH)3: P21/c; a = 1166.6(1), b = 786.4(1), c = 997.8(1) pm, β = 106.91(1)°; Z = 4. K3(PO2NH)3: R3̄; a = 1271.4(2), c = 1017.9(2) pm, Z = 6). In Ag3(PO2NH)3the cyclic anion is markedly distorted because of interactions between Ag+and one nitrogen atom of the anion. In K3(PO2NH)3the trimetaphosphimate ring shows a chair conformation and two cyclic anions are connected to each other by hydrogen bonds. DTA/TG investigations show thermal decomposition above 275 and 250 °C for 1 and 2, respectively.

Pure, stoichiometric, hydrogen-free, and crystalline phosphorus nitride P3N5 has been obtained for the first time by reaction of (PNCl2)3 and NH4Cl between 770 and 1050 K. The compound has been characterized by elemental analyses, ³¹P and ¹⁵N MAS NMR, EXAFS, IR spectroscopy, X-ray powder diffraction, and electron microscopy. In the solid a three-dimensional cross-linked network structure of corner sharing PN4 tetrahedra has been identified with ²/5 of the nitrogen atoms bonded to three P atoms and ³/5 of the nitrogen atoms bonded to two P atoms. By electron diffraction (ED) and high-resolution transmission electron microscopy (HRTEM) two distinguishable modifications α-P3N5 and β-P3N5 have been identified which differentiate only by the stacking order of identical sheets similar to the polytypes of SiC.

A novel synthetic approach is presented which starts from silicon diimide Si(NH)2and makes available a manifold variety of novel nitridosilicates. Structurally these nitridosilicates represent a significant extension of the family of oxosilicates. With respect to their outstanding chemical and physical stability nitridosilicates might be of particular interest for the development of novel inorganic nitridic materials.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Gram amounts of KO3can be prepared by reaction of gaseous ozone/oxygen mixtures (2 vol.% O3) with KO2in a temp.‐controlled (+10 to ‐50 °C) fluidized bed reactor followed by extraction with liquid ammonia (100% yield based on KO2).

The title compound, synthesized as outlined in the scheme (yield not given), crystallizes in the orthorhombic space group Pbca with Z = 8. In the crystal, a crystallographically independent molecule SP(NH2)3is found, which shows non‐crystallographic point symmetry Cs.

The title ozonides show Curie‐Weiss behavior above 50 K. Magnetic moments of 1.74 μB (KO3, CsO3) and 1.80 μB (RbO3) calculated from the Curie‐Weiss straight lines correspond to spin‐only moments expected for isolated O3‐species with one unpaired electron.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

Pure LiPN2is prepared by solid state reaction of an equimolar mixture of Li3N and P3N5(800 °C, tungsten crucible, N2atmosphere).

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.

ChemInform is a weekly Abstracting Service, delivering concise information at a glance that was extracted from about 100 leading journals. To access a ChemInform Abstract of an article which was published elsewhere, please select a “Full Text” option. The original article is trackable via the “References” option.