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Das Sialon SrSiAl2O3N2 wurde durch Umsetzung von Siliciumdiimid, Aluminiumnitrid und Strontiumcarbonat unter N2‐Atmosphäre im Hochfrequenzofen bei 1650 °C in grobkristalliner Form erhalten. Nach der Röntgenstrukturanalyse an Einkristallen ist die Titelverbindung isotyp mit LnSi3N5 (Ln = La, Ce, Pr, Nd). SrSiAl2O3N2 (P212121, a = 491,98(6), b = 789,73(7), c = 1134,94(18) pm, Z = 4, R1 = 0,0439, wR2 = 0,0939). Im Festkörper liegt eine Raumnetzstruktur allseitig eckenverknüpfter SiON3‐, AlO3N‐ und AlO2N2‐Tetraeder vor. Gitterenergetische Rechnungen mit dem MAPLE‐Konzept bestätigen die eindeutige kristallographische Differenzierbarkeit zwischen N‐ und O‐ bzw. Al‐ und Si‐Atomen (Al–O: 167,4(5)–170,6(6); Al–N: 175,4(6)–179,4(6); Si–O: 171,2(6); SiN: 176,7(6)–179,6(6) pm). Die Sr2+‐Ionen sind in den Hohlräumen des (SiAl2O3N2)2–‐Gerüstes positioniert (Sr–O: 250,4(6)–304,2(6); Sr–N: 287,4(6)–318,2(6) pm).

A novel synthetic approach is presented leading to hitherto unknown nitridosilicates, oxonitridosilicates, oxonitridoaluminosilicates, carbidonitridosilicates, as well as nitridoborates and oxonitridoborates of rare earth elements, alkali, and alkaline earth metals. Typically, the respective metals were reacted with silicon diimide, aluminum nitride, or poly(boron amide imide), respectively, under pure nitrogen atmosphere utilizing a radiofrequency furnace. Usually, the compounds are obtained within short reaction periods as coarsely crystalline products. Zink nitridophosphates of the sodalite structure type were obtained by the reaction of phosphorus nitride imide with zinc or zinc chalcogenides, respectively. Several molecular metal silylamides and imides containing nitridobridges between the metals and silicon were obtained by the reaction of differently chlorinated disilazanes with metal chlorides. During these investigations hitherto unknown bis(trimethylsilyl)ammonium salts have been discovered. Furthermore, we report about the synthesis of N‐silyl metal hydrazides.

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